Kia Khaleghpour - IR Jim Mullen - President and CEO Evan Beckman - SVP of Immunology R&D Bob Hamm - COO Paul Clancy - CFO and EVP of Finance Rick Munschauer - VP of US Neurology Medical Affairs

Karim De Felipe - Citigroup Eric Schmidt - Cowen and Company Joel Sendek - Lazard Capital Markets Rachel McMinn - Banc of America Geoff Meacham - JPMorgan Nick - Barclays Capital Joshua Schimmer - Leerink Swann Gene Mack - Soleil Securities Ian Somaiya - Piper Jaffray Bret Holley - Oppenheimer Chris Raymond - Robert W. Baird & Company Jason Zhang - BMO Capital Markets

Thank you and welcome to Biogen IDEC’s first quarter 2010 Earnings Call. Before we begin, I encourage everyone to go the Investor section of biogenidec.com to find the press release and related financial tables, including a reconciliation of the non-GAAP financial measures that we’ll discuss today.

We’ve also posted slides on our website that outline the topics discussed on today’s call. As usual, we’ll start with our Safe Harbor statement.

Comments made in this conference call include forward-looking statements about our expected future results and about healthcare reforms, our operational goals, the market potential of our product, and pipeline advancements. These statements are subject to risks and uncertainties, which could cause actual results to differ materially from expectations.

You should carefully review the risks and uncertainties that are described in our earnings release, and in the risk factors sections of our most recent annual and quarterly reports filed with the SEC. We do not undertake any obligations to publicly update any forward-looking statements.

Today on the call, I’m joined by Jim Mullen, CEO of Biogen IDEC; Dr. Evan Beckman, Senior Vice President of Immunology R&D, Bob Hamm, Chief Operating Officer; and Paul Clancy, CFO and Executive Vice President of Finance.

We'll also be joined for the Q&A portion of the call by Dr. Rick Munschauer, Vice President of US Neurology Medical Affairs Now, I’ll turn the call over to Jim Mullen.

Thank you, Kia. Good morning everyone and thank you for joining us.

During first quarter of 2010, we continued to execute on our business strategy and positioned the company for growth over the long-term. Total revenue increased 7% on a year-over-year basis to $1.1 billion driven by 32% year-over-year TYSABRI revenue growth.

Two items negatively impacted first quarter earnings, a $13 million increase in rebates mandated by the Patient Protection and Affordability Care Act, and a $14 million write-down on our investment in AVEO Pharmaceuticals. Taken together these items reduced EPS by $0.07.

Our non-GAAP diluted EPS for the first quarter of 2010 was a $1.08, an increase of 3% on a year-over-year basis. The company generated $337 million in cash flow from operations and ended the quarter with a $2.2 billion cash balance, and as of the end of March 2010, we estimate that we now have more than 50,000 patients in commercial and clinical TYSABRI therapy.

On an operational basis in the first quarter, we launched three new TYSABRI trials that surpassed head-to-head comparative trials that determine the effect of switching from Copaxone or Rebif to TYSABRI and stratify one and two to test the utility of JC virus antibody assay through risk stratification. These studies are the latest in a series of investments we made to clarify the benefits and risks of TYSABRI.

We completed a share repurchase program announced in October of last year, which returned $1 billion in cash to our shareholders and received board approval to purchase an additional 1.5 billion of shares. We continue to make significant strides in the development related to the clinical pipeline.

Last week, we updated the medical community on our progress of our neurology pipeline at the Annual American Academy of Neurology meeting, where we presented 38 posters on our broad and deep MS pipeline. For more detail on our pipeline and information, we presented at AAN, I will now hand the call over to Dr.

Evan Beckman, our Senior Vice President of Immunology Research and Development. Evan?

Thank you, Jim. I would like to begin with an update of our registration trial.

We continue to make good progress on advancing and developing our late stage clinical pipeline and expect data on some of these programs as early as next year. Preparations are underway to initiate the phase 3 trial Daclizumab.

This is DECIDE trial into two-year study of Daclizumab in RRMS patients with AVONEX is the comparator. We look forward to updating you with further details of this study.

As previously announced both BG-12 registrational studies DEFINE and CONFIRM have completed patient enrollment and the trials continue on plan. We expect data from DEFINE during the first half of 2011 and from CONFIRM during the second half of 2011.

We continue enrolling patients in the ADVANCE study of PEGylated interferon beta-1a and in a Phase 3 study of GA101 for frontline chronic lymphocytic leukemia in combination with Chlorambucil. Enrollment for a second registrational trial in Rituxan-refractory indolent Non-Hodgkin’s lymphoma patients is planned to start during the second quarter of 2010.

Patient enrollment for B-LONG, which is the registrational trial for our long-acting, recombinant Factor IX candidate in hemophilia B continues to progress well. Last week, we shared important data on our neurology franchise at the American Academy of Neurology annual meeting, where we demonstrated the strength and the quality of our neurology pipeline with 38 company-sponsored platform and poster presentations.

Nearly four years after its reintroduction in the US and initial launch in the EU, we continue to demonstrate the powerful efficacy of the TYSABRI offers relapsing multiple sclerosis patients. Key data presentations reinforced the growing body of evidence that TYSABRI is an important therapeutic option for patients and may lead to overall improved quality of life for MS patients, from improvement and physical function, cognition and visual function to reduce fatigue.

We take the issue of PML very seriously with each case of PML there is the potential to learn something new about this rare, but serious adverse event. To this point, Dr.

Rick Rudick presents a data from our retrospective analysis of patients enrolled in the STRATIFY trial which show that TYSABRI does not lead to substantial changes in the presence of JC virus DNA in blood or urine samples of MS patients. During the first quarter, we initiated three important trials related to TYSABRI, STRATIFY 1 and 2 and SURPASS.

As discussed during the platform presentation at AAN, we have developed the blood test that detects antibodies to the JC virus, the virus that causes PML. The presence of the antibody to the virus suggests that a patient has been previously exposed to the JC virus.

While the data are still preliminary, this assay may provide a tool for physicians to stratify the risk of PML in their MS patients. To recap what we know today, for 13 TYSABRI treated PML patients, where we have baseline plasma samples, all 13 of them were antibody positive for one to three years before developing PML.

If antibodies status was not a factor for developing PML, we would only have expected six or seven to be positive based on our data that 54% of MS patients have been exposed to the virus previously. So, our hypothesis is that there may be a lower risk for developing PML in TYSABRI treated MS patients who are antibody negative.

To confirm this hypothesis, we have initiated two clinical trials. STRATIFY 1 is designed to determine the percentage of the MS patient population that’s positive for JC virus antibodies as well as the false negative rates for the blood test.

We expect to enroll 1,000 patients in this trial, inclusion criteria are current TYSABRI patients enrolled in [Touch] or patients who are not currently on TYSABRI but are considering beginning TYSABRI treatment. For this trial, we will be testing for JC virus antibody in the blood and testing for the presence of JC virus DNA in the urine every six months for two years from the time of enrollment.

STRATIFY II is designed to evaluate whether the incidents of PML and TYSABRI patients were negative for the JC virus antibodies is less than the incidents among TYSABRI patients who were positive for the antibodies to JC virus. STRATIFY II is expect to enroll a minimum of 8000 patients and is open to all types of prescribers.

In this trial we'll be testing for the JC virus antibody only in the blood and on an annual basis for two years from their time of enrollment. Our goal is to ultimately provide neurologist and MS patients with tools to stratify risk.

Our thinking here is that within the context of the clinical trial, whether it's prospective analysis of the data with the best opportunity to validate and determine the clinical utility of this assay. Our hope is that over the long-term the JC virus assay may help physicians to make better treatment decisions for MS patients.

Moving onto SURPASS, our objective with this study is to provide a new model for making optimal treatment decisions in order to improve the outcomes of patients with MS. SURPASS will be the largest prospective study to provide comparative data regarding the management of breakthrough disease in MS.

Amongst MS specialists there is an evolving standard of care that when a patient on first-line MS therapy presents with either clinical or MRI evidence of disease activity, modification of treatment needs to considered. Yet, there is no evidence confirming whether switching MS therapies results in improved outcomes.

In the SURPASS trial, we're enrolling MS patients initially treated with the Rebif or Copaxone for least six months. We subsequently experienced either a clinical attack or two or more new MRI lesions.

Patients would then be randomized to one of three arms. The first is to continue on the initial therapy, the second converting to the other first-line therapy or third converting to TYSABRI.

SURPASS has a target enrollment of 1800 patients, at 230 sites worldwide, we expect they will provide important data on whether early identification of breakthrough disease, and subsequent modification of therapy improves patient outcomes. We expect the study to be completed in 2013, our goal with SURPASS and the STRATIFIED trials is that combined these studies will provide physicians with powerful tools for informed treatment decisions, such as improved techniques for stratifying the risk of PML in MS patients on TYSABRI.

Now an update on the rest of our pipeline, during the first quarter we along with our partner Roche decided to suspend treatments of patients in the Ocrelizumab rheumatoid arthritis program. This decision followed the recommendation of the independent Ocrelizumab RA & Lupus Data and Safety Monitoring Board, based on their assessment that safety risk, outweigh the benefits observed in these specific patient populations.

We recently announced that the primary endpoint was met in the Phase III SCRIPT study of Ocrelizumab in the TNF IR RA patients. The future of the Ocrelizumab RA clinical programs is currently under review as we and our partner will have to consider these recent results along with the complete safety data set The Ocrelizumab program in relapsing remitting MS remains ongoing at this time.

However the MS Data Safety Monitoring Board will be reviewing the safety data, from the RA Lupus and MS files. We previously announced that the MS study achieved its primary end point and we continue to discuss the next steps for Ocrelizumab MS program with our partner Roche.

Turning to oncology. As you may recall during the third quarter earnings last year, we announced that we had stopped patient recruitment, in the lumiliximab LUCID trial.

We recently reviewed the data for the lumiliximab trials in both relapsed and the front line CLL and determined that the results do not support continuing the program. Next an update on our blood factor programs.

As we announced in January, the global registrational trial for a long-acting recombinant Factor IX candidate in hemophilia B continues to enroll patients. We planned to present results of the Phase 1/2 Factor IX study in July at the World Federation of Hemophilia meeting in Buenos Aires.

Additionally, the Phase 1/2 study of our long-acting recombinant Factor VIII program is progressing well and we expect to redial from this study later this year. Recombinant Factor IX Fc is the first major blood factor innovation since the development of recombinant drugs in the 1990.

We believe that our long-acting blood factor programs have the potential to significantly improve the lives of people with hemophilia and as a result expand the hemophilia market opportunity. Recombinant Factor IX Fc offers the hope of less frequent injections and prolong protection from bleeding compared to existing therapies.

Our goal in developing the long-acting blood factor candidates is to change the treatment paradigm in hemophilia with more prophylactic usage. Current short-acting treatments require in two to three infusions per week for hemophilia B and three to four infusions per week for hemophilia A, don’t lend themselves to easy prophylactic usage.

Well, most children with severe hemophilia are already on prophylactic regimen based on the compelling outcome studies giving frequent IV infusions to children, places are significant burden on parents. For young children prophylactic dosing also frequently requires placement of a central catheter or port, which introduces risk of serious infection.

For adults with hemophilia, episodic or on-demand treatment is more common despite the clinical benefits to prophylaxis. Recombinant Factor IX Fc has the potential to lower the hurdle for prophylactic treatment of hemophilia B in both the pediatric and adult populations.

Looking forward, we expect to announce data readouts in seven clinical studies throughout the remainder of this year as well as data presentations at several medical meetings. We expect to readout from the TARGET study, which is the Phase II trial of Galiximab in combination with RITUXAN in follicular NHL during the fourth quarter of this year at a medical meeting.

We have completed enrollment in two out of three pivotal studies for Lixivaptan in hyponatremia. These multinational studies include the balance trial, a 650 patient study that enrolled patients with heart failure and the Leber trial, a study of in-patients with the syndrome inappropriate antidiuretic hormone hypersecretion, or SIADH.

Top-line data readout for these two studies is expected during the second half this year. We continue to make advances on our other pipeline programs with readouts for the Phase II trials of AVONEX in ulcerative colitis, and BG-12 in rheumatoid arthritis, both expected during the second half of 2010.

We expect to present data from four of the Phase III studies of Ocrelizumab in RA at the American College of Rheumatology Annual Meeting. These include data from the STAGE, FEATURE, FILM and SCRIPT trials.

For the Ocrelizumab MS program, we previously announced positive top-line data from this trial in Q4 2009 and in October of this year, we planned to present data at ACTRIMS. Data announcement from the Phase III PRIMA study of RITUXAN as a [latent] therapy for indolent non-Hodgkin lymphoma is planned in oral presentation of the upcoming ASCO Annual Meeting.

Last September, we announced that this study met its primary endpoint of progression free survival during a pre-planned interim analysis. We, along with our partner Roche, also planned data presentations at upcoming medical meetings on our anti-CD20 monoclonal antibody, designed specifically for use in oncology, GA101.

Specifically, we expect data presentation from the Phase II portion of the Phase I/II study of GA101 an indolent NHL in June at the European Hematology Association meeting in Barcelona. Also, we planned to present data from the Phase II portion at NHL and CLL patients at the American Society of Hematology meeting in December.

Along with advancements on our clinical programs, we continued to make progress on our regulatory efforts. Recall that earlier in Q1 we received FDA approval for RITUXAN in combination with fludarabine and cyclophosphamide for previously treated and untreated CD20-positive chronic lymphocytic leukemia.

We continue efforts aimed at expanding the RITUXAN label with additional indications. Last month we submitted supplemental Biologics License Application to the FDA and EMA to expand the RITUXAN label in non-Hodgkin's lymphoma to include maintenance treatment for previously untreated patients with advanced follicular lymphomas.

We based our submissions on Phase 3 PRIMA study data. The US regulatory filings for RITUXAN in ANCA-associated vasculitis also remained on track for the second half of this year.

We continue to expand on the regulatory efforts with prolong release Fampridine outside of the US. We have filed for approval in the EU, Canada, Switzerland, Australia and New Zealand and expect to have more filings.

We are excited for the anticipated ex-US launch of prolonged release Fampridine. Data presentations at AAN highlighted consistent improvements in average walking speed for MS patients last week.

In conclusion, we continue to make progress in our pipeline and our R&D organization continues to perform well. We are currently supporting 76 trials with more than 4700 patients across more than 1200 sites worldwide.

Our efforts position us well for future growth and we look forward to providing you updates on new developments in the quarters ahead. With that, I will now pass the call over to Rob Hamm, our Chief Operating Officer.

Thank you Evan. In the first quarter, AVONEX, TYSABRI and RITUXAN, generated combine worldwide revenue for Biogen Idec of 1.1 billion, up 7% year-over-year with continued growth in our core MS business more than offsetting a decline in RITUXAN royalty revenue.

As Jim mentioned, TYSABRI exceeded 50,000 patients. While TYSABRI continued to add patients during the quarter, patient growth during the first half was modest.

We saw a rebound in March when we added more than 190 patients per week. Importantly the moderation in patient growth during the first half of the quarter was a result of a decrease in new patient starts not an increase in discontinuations.

We have seen this pattern in the past when physicians and patients have taken the time to absorb new information regarding PML risk. In this case, we suspect a label change to reflect the increase risk of PML with increased duration of therapy may have been the cause.

Also, we have seen a deceleration in patient growth in Germany where there is still a high level of PML discussion. The safety concern in Germany may have been amplified by Dear Doctor letters sent to physicians during the first quarter.

We also see evidence of a modest increase in drug suspensions. In order to better understand the impact this is having on TYSABRI use, we regularly ask our patients and physicians about their dosing preferences, while at the same time monitoring our TOUCH data on US compliance in discontinuations.

What we have found is that most of the physicians who discuss this option with their patients allow them to make their own decisions based on their own unique situation. Based on our data from the TOUCH program and from physician and patient interactions, we estimate that at the end of March, less than 10% of all US TYSABRI patients were under drug suspension.

We plan to continue to follow this trend closely. The impact of this can be seen as a modest decline in net revenue for patient as most physicians in the US do not discontinue their patients from TOUCH during drug suspension.

Since our re-launch in 2006, we have had questions about the impact of research initiatives on TYSABRI's adoption. Most recently there has been interest in our work on the JCV antibody aspect.

Long-term, we believe that it is important for neurologist in MS patients to have more information clarifying TYSABRI’s benefit and risk for individual doctor-patient benefit risk discussions. So while our net patient growth may moderate to observe this new information over the short-term, we've disciplined ourselves to keep perspective onwards is best for the long-term adoption of the product.

Now an update on AVONEX, the franchise generated $593 million in global revenue during the first quarter of 2010, an increase of 7% year-over-year. AVONEX Q1 sales benefited partially from a 5.5 price increase in the US on 26 February.

Our new US commercial team is now largely in place and showing renewed energy and focus. The new US team has accessed our US AVONEX commercial strategy and indentified three areas we can address in order to arrest the decline of our AVONEX US market share.

The first is sales force effectiveness, we need to have reemphasized clinical selling and focus calling programs on key customers. We were examining multiple options to increase our interactions with physicians.

The second is tactical marketing execution, AVONEX has compelling long-term efficacy data but that message has been lost over the past few years. Our CHAMPIONS ten-year data brought that message back into focus and is starting to resonate with physicians.

Now we need to build on that as we continue to mass evidence of AVONEX long-term efficacy. The third area we need bear leverage is our patient services.

Biogen Idec has been a pioneer in this area and we need to reestablish the premise of this as a competitive advantage. We have an extremely talented organization and research channel partner in (Carolina) that has been doing some great work with therapy support.

We know that patient participation program increases product compliance. Over the next few months we will be launching programs to increase patient participation in therapy support.

Outside the US, our sales force has been highly effective and our marketing message has been cleared in step with the local market. We have a strong international leadership team in more than a dozen years of experience selling directly to markets outside the US.

Structurally one thing that has facilitated our effectiveness overseas has been our affiliate model. We have a local presence in each of our direct markets with experienced sales force and programs tailored to local patients and physicians.

In my opinion these are the factors that make AVONEX the number one MS therapy outside the US and inform our updated strategy within the US. Next, an update on RITUXAN.

RITUXAN Q1 revenues to Biogen Idec were $255 million, down 9% year-over-year. This decline was driven by the continued exploration of royalties on revenues outside the US.

Our US RITUXAN profit share was up 12% on a year-over-year basis and 4% on a quarter-over-quarter basis driven by increased demand in the hematology and oncology settings and some restocking in the channel. Finally, quick update on prolonged release Fampridine, marketed as AMPYRA in the US by Acorda Therapeutics.

Our plan for launching outside the US continues on schedule. During the first quarter, we assembled an international prolonged release Fampridine advisory board of neurologists from 14 countries.

This advisory board provides scientific input in the potential prolonged release Fampridine launch and subsequent product life cycle management. The advisory board held their first meeting in January in parallel with our supply chain team continues preparation to enable appropriate compassionate use programs and name patient supply.

We look forward to upcoming discussions with the regulators now that launches potentially less than a year away. With that, I will now turn the call over to Mr.

Paul Clancy our Chief Financial Officer.

Thanks, Bob. I'll review our 2010 first quarter financial performance.

Our GAAP financials are provided in tables 1 and 2 of the earnings release table 3, includes the reconciliation of GAAP to non-GAAP results. The primary differences between our GAAP and non-GAAP results for the quarter were $49 million related to the amortization of acquired intangibles, $40 million for the contingent consolidation payment associated with the Syntonix acquisition, $12 million from employee stock option expense and $5 million for severance and restructuring.

All of these, offset by a $27 million tax impact on these items. Our GAAP diluted EPS was $0.80 in Q1 2010.

Now, I'll move on to the non-GAAP P&L operating performance of Biogen IDEC, which we believe better reflects the ongoing economics of the business and reflects how we manage the business internally and set operational goals. Our Q1 non-GAAP diluted EPS was $1.08.

The quarter was negatively impacted by two items. First, we incurred a $14 million charge resulting from the impairment of our strategic investment in AVEO Pharmaceuticals following their initial public offering in March.

Second, we were impacted by US Healthcare Reform. Specifically, revenues were reduced by $13 million due to the recently approved Patient Protection and Affordable Care Act.

In the quarter, we specifically incurred additional discounts from three changes. First, the change in the minimum Medicaid rebate from 15.1% to 23.1%, which took effect retroactive to January 1st.

Second, the expansion of Medicaid rebates to managed care organizations that dispense drugs to Medicaid beneficiaries, which took effect on March 23rd as the law was enacted, and third, the expansion of 340B Public Health Services Drug Pricing Program, which provides outpatient drugs at reduced rates to include certain hospitals, clinics and healthcare centers. This was effective retroactive to January 1st.

These additional discounts impacted each of our products as noted on our slide in the earnings presentation. The AVEO impairment combined with the impacts of healthcare reform, unfavorably impacted EPS by $0.07.

Now, let's move to the first quarter results in a bit more detail starting with revenue. Total revenue for the first quarter of 2010 was $1.1 billion, a 7% growth over the first quarter of 2009.

Q1 product revenue grew double-digit to $824 million, a 12% growth over Q1 2009. I will start now going through our products revenues with AVONEX.

Q1 AVONEX worldwide product revenue was $593 million, a 7% increased over Q1 2009. US AVONEX product revenue in the first quarter was $350 million, a 3% increase versus prior year.

US AVONEX inventory in the channel ended at about two-and-a-quarter weeks in the first quarter. In Q1, units sold in the US declined approximately 9%, as compared to Q1 2009.

This was offset as Bob noted by price increases. Unemployment continues to impact our US AVONEX trend as free goods once again increased.

Q1 international AVONEX products sales were $243 million, a 13% increase over Q1 2009. In Q1 2010, units sold outside the US increased approximately 4% as compared to prior year.

Q1 TYSABRI worldwide product sales were $219 million for Biogen IDEC, a 32% increase over Q1 2009. As Bob mentioned TYSABRI patient growth moderated in the quarter likely the lagged effect of label discussion with FDA and EMEA.

Nevertheless, we are encouraged by the trajectory we saw in the last month of Q1 specifically we estimate our net patient adds in the month of March pick backup to average approximately a 190 per week. In the US, end-user TYSABRI sales totaled $135 million for the first quarter, a 17% increase over Q1 2009.

Biogen Idec booked $60 million of revenue of this amount. Q1 international TYSABRI product revenue was $158 million, a 42% increase over Q1, 2009.

Q1 (Fampridine) revenue was $13 million. Now moving on to the RITUXAN collaboration revenues referred to as revenue from unconsolidated joint business.

We recorded $255 million in revenue for the quarter, representing a decrease of 9% on a year-over-year basis. Our RITUXAN revenues have broken down into three components.

First, our share of the net US RITUXAN profits, net US RITUXAN sales were $687 million in the first quarter of 2010, up 7% versus prior year, benefiting from demand in channel restocking. Our Q1 2010 profit share from that business was $200 million, up 12% versus prior year.

Second, we received revenue on sales of rituximab outside the US and in Q1 this was $38 million, down 54% versus prior year as royalties from individual countries have expired. Third, in the first quarter, we've reimbursed $16 million for selling and developing cost incurred related to RITUXAN.

Royalties were $26 million for the first quarter 2010, an 8% increase year-over-year. Now turning to the expense lines in the non-GAAP P&L, which includes the adjustments that I described earlier.

Q1 COGS were $97 million or 9% of revenues, benefiting from fewer inventory write-offs. Q1 R&D expense was $303 million or 27% of revenues.

This represents a 9% increase over the prior quarter and 10% increase over the prior year, due primarily to an additional $19 million in expense we assumed as a result of a restructured collaboration agreement with Swedish Orphan Biovitrum for our blood factor programs. In essence, we are now bearing the full development and manufacturing expenses for the Factor IX and Factor VIII programs in exchange for more favorable downstream economics in streamlined roles.

Additionally, at our large scale facility in RTP, we redeployed the manufacturing activity to clinical programs away from commercial production which reduce the amount of expense that is normally capitalized to the balance sheet. This adds an additional $30 million of R&D expense during the quarter.

These two impacts were somewhat offset favorability from recent program decisions. I'd also note that during the second quarter this year, we anticipate that we may make a $30 million milestone payment to Facet Biotech, our partner in Daclizumab due upon initiation of the Phase 3 DECIDE trails.

Q1 SG&A expense was $234 million or 21% revenues. As mentioned during our last call, our SG&A expenses percentage of revenues may average as much as 22% in total for 2010, as we prepared to defend our MS franchise, against potentials new competitors.

Continuing down the P&L, our collaboration profit sharing line totaled $64 million in expense for the quarter, representing our payments of profits outside the US to Elan and the reimbursement of third-party royalties incurred by Elan outside the U.S. Other income and expense for the quarter was a loss of $8 million driven by the $14 million charge from the impairment of our investment in AVEO Pharmaceuticals as previously mentioned.

Our cash in marketable securities position ended the quarter at $2.2 billion, down from year end, mostly due to purchase of treasury stock. Our Q1 non-GAAP tax rate was approximately 25%.

The Q1 tax includes the $6 million one-time benefit related to restructuring of an international entity. This brings us to our Q1 non-GAAP diluted recurring per share, which were $8.

Now let me share the progress we've made with respect to our share repurchase program. During the first quarter of 2010, we repurchased and retired 10.5 million shares at a total cost of $578 million As a result we completed the billion dollar share repurchase program announced during the fourth quarter of 2009.

In total since the October authorization we purchased 25.3 million shares for a total cost of $1.3 billion including approximately 6 million shares earmarked for share stabilization. Biogen Idec’s average shares outstanding were approximately 273 million for the first quarter.

Last week the board approved an additional $1.5 billion share repurchase program with the objective or returning excess cash to share holders. The authorization is open ended and our intention is to execute the program in the open market at a more likely and more deliberate pace.

Our decision to repurchase more shares is influenced by a number of factors including the continued improvement in the credit markets, our outlook in the cash flow generation of the enterprise and the potential for our product initiatives in pipeline maturation. We continue to have the flexibility in capacity to pursue meaningful strategic investments.

Turning to the full year outlook, we’re leaving our financial guidance unchanged from previous communication. We estimate healthcare legislation, will reduce our revenue by approximately $70 million to $90 million for the year or about 2%.

These reductions are due to the increase in medicate rebates, the expansion of hospitals eligible for 340(B) pricing and the extension of medicate rebate to managed care organizations. Nevertheless, the longer-term impact on our business can be less unfavorable as expansion of patients who are currently uninsured and prescription drug coverage for patients in Medicare part D, Doughnut Hole takes affect in future years and Biosimilar legislation including the 12-year data exclusivity on biologic therapies can be quite positive.

The balance of your market impact of both, potential new competition and data provided in the context of our JCV Antibody Assay trial is equivocal. We'll monitor closely the TYSABRI trends over the next few months as patients and physicians adjust to new information.

Regardless, we believe that our initiatives to provide more clinical data on the benefit risk equation can poise TYSABRI for strong growth over the long-term. In conclusion, our core business delivered a solid quarter.

Total product sales grew by 12%. We are marking progress on our late-stage pipeline and we continue to generate strong free cash flow.

We faced new headwinds this quarter, yet, we'll continue to keep our focus on the long-term. From that perspective, we are in an enviable position.

Our pipeline feature six products in registrational trials, we have several intriguing TYSABRI initiatives underway, and we generate sound cash flow allowing us to return capital to shareholders. I'll now hand the call over to Jim for his closing comments.

Thank you, Paul. In summary, the first quarter introduced some top line pressure that we are aggressively working to counter, but we continue to deliver bottom line growth and strong cash flow.

We're focusing on advancing our enviable late stage pipeline with six programs in registrational trials. Overall, we made progress on a number of strategic initiatives intended to position the company for long-term growth.

With that Kia will now open up the call for Q&A.

Operator, we are ready to open up the call for Q&A, we'll ask that you please limit yourself to one question and reenter the queue for follow-up question. Please state your name and company affiliation.

Operator, we are ready for the first question.

It's actually Karim De Felipe calling in for Yaron. I have a question on AVONEX.

I have a question on AVONEX. Regarding the sequential decline in sales, even despite the price increase, I was wondering if you could give us more color on what the volume trends were for the quarter?

This is Paul. Thanks, Karim.

In the United States, we saw year-over-year decline of about 9%, outside the United States increase of mid single-digits. I think the trend in the United States does partly to continued pressure from unemployment and this is actually our free drug program increasing for AVONEX in the quarter versus the over the last couple of quarters.

Got it. Could you also give me the FX impact for AVONEX?

The FX impact for the total business was about a positive 3% on a year-over-year basis and that is net of hedging in net across all of the products.

Yes, just wondering about the share repurchase plan. It’s quite substantial what’s should we read into that is anything regarding strategic alternatives, kind of broader use of cash etcetera and then Paul, if you could provide the share count at the end of Q1 that will be very helpful.

Yes, just wondering about the share repurchase plan. It’s quite substantial what’s should we read into that is anything regarding strategic alternatives, kind of broader use of cash etcetera and then Paul, if you could provide the share count at the end of Q1 that will be very helpful.

I'll start with the backend questionnaire. The average shares outstanding on diluted basis was approximately 273 million were probably about 4 million or 5 million shares underneath that as of March 31, 2010.

I wouldn’t read too much into it. With respect to the strategic agenda, we continue to work earnestly as alternatives for the strategic agenda.

I just point to the comment I made that we still have adequate financing capacity. I think our confidence in the credit markets, that’s right or wrong, is certainly much better than it was a year ago.

So you still want to judge us in terms of our capability with respect to financing capacity as well and I really just point you the fact that it does underscore a strong free cash flow generation for the enterprise.

I had a question about the TYSABRI drug suspensions. I am just a little confused here because clearly the -- what you said about the new patient adds in March shows a trend upward but yet if I compare what you said about drug suspensions now versus last quarter, it looks like they are up.

I know it's from last quarter, say there is about 5% patients on drug suspensions and now it's about 10%. So can you reconcile that, please?

Sure. This is Bob Hamm.

What we saw, beginning in the fourth quarter was the duration story unfolding was a slight increase in the suspension story. I don’t believe we said TYSABRI, look at single digits at the time high single digits and we have looked at that closely.

The issue is we only have data for the US which is now only half the patients. So what we are saying is what we can gleam from the US data only, so that’s about all we can say on it at this point.

The other thing Joel I would just add is that many of those patients that Bob referred to as in drug suspension can stay in our patient database in the United States. So the reconciliation between the two is really more made-up in the average share price per patient.

I got two questions. One, can you comment on the CEO search, and Jim what you are going to do?

Nobody is hired before Jim and then, the second question is just on the TYSABRI fourth quarter patient number, they look a little bit different than what you had stated last quarter. I am wondering what the difference is there?

We will take that in reverse order. Paul you want to.

Thanks for the question I appreciate it. We will, as a matter of course, always try to update the best estimates even when we look backwards in the patient database.

In the United States, that rarely results in any change, what you would note though is that in our international patient database we made a change to correct for our best estimates. That is just simply a function of the fact that internationally the patient estimates are just that.

It is estimates that are little bit triangulated but what the most important piece of data is, the shipments going out. I would note as it relates to that those changes that we made which brought down the patient numbers in international at the year end 2009 were largely owing to Germany, which Bob had pointed out, which we actually see as probably the one market outside the United States that is relatively flat.

If you take the trends outside of the Germany a number of the major countries are doing quite well and continuing to add patients.

Rachel with respect to the CEO search, so just to take people back, there is a Board search committee composed of four Board members. They have been active in the search and interviewing candidates and I think they are, they're simply very cognizant of the June date and working towards that.

If there is not somebody in place by June, that will be another conversation with the Board but there is not a specific plan for that.

Question for you on the PML rate, we are above one and 1000 in patients on drugs for over a year and just curious what the strategy is when the overall plus marketing rate exceed this and is there an active dialogue with FDA or EMEA ahead of it?

This is Rick Munschauer. We have been monitoring the overall incidents those by duration of therapy and by effects quite carefully.

These are very small numbers and we really at this point don’t think that there has been a variability there that’s outside of the expected variability on a month-by-month basis given the relative rarity of the event and certainly we are in constant communication with the FDA about this information that’s widely available and discussed.

Just a follow-up, to an earlier question on the JC virus assay, do you guys feel post AAN that you have more validation work to do on the assay or is that now a matter of just accumulating data on as many patients as possible? Thanks.

We are very encouraged in our preliminary studies that 13 out of 13 patients for which we had samples stored away, who went on to develop PML were indeed positive by that assay. That has led us to the STRATIFY 1 and STRATIFY 2 trials, which will formally cap that high positives this over time.

A total of about 9,000 patients will be entered in to that trial and we do feel that trial will give it the bottom line information about the value of this assay in stratifying the risk for PML.

This is (Nick) calling in for Jim. With respect to the STRATIFY 1 and 2 trials, I can’t remember from the quote, did you say that patients and physicians would receive the data in a real-time fashion back in STRATIFY 1?

We heard that that was not going to happen now, and on the STRATIFY 2, I think I've heard you just say around 9,000 patients, but I've also heard you say 28,000 patients, so all of the patients who are receiving TYSABRI.

With response to your first question, yes, the protocol has written now. It does share the information with the doctor and the doctor can share with the patient when you're enrolled in the STRATIFY 1 or STRATIFY two trials.

We have been in active discussion with the FDA about this and at this point the information is still, but the information will be share going forward with that. In terms of the study size, STRATIFY 1 is 1,000 patients that is designed to determine the false negative rate of our assay.

STRATIFY 2, we project will be about 8,000 patients, we'll see in terms of that trial that progresses whether we're obtaining the appropriate amount of information to achieve our overall endpoint and that is establish the solidity of this assay and stratifying risk.

Will you send back to the physician? It will just be a yes, no or it has a level and then the physician and the patient scratch their heads and say what do we do now?

Will you provide any guidance? You can't provide any guidance as to what they should do..

Good question. The report factor of the physician will be either positive or negative, and it is a yes/no kind of response.

There is an intermediate zone where we do confirmatory assay, so the physician will know yet an intermediate test was done and this was positive or negative in those patients that are [borderline]. There is obviously no guidance from the company and this is a protocol, what a particular physician does with this information will be done in concert with his discussion with the patient.

That intermediate test, is that a most sensitive allies with any run?

It’s a more sensitive allies to make sure that we capture all those patients, who are within a certain threshold of being positive.

What trends are you seeing and expecting in ex-US reimbursement rates for your core MS franchise? Do you see new country opportunities in the emerging markets providing sufficient oversees growth to offset reimbursement in pricing challenges that you had in Europe?

It’s Bob Hamm. The recent announcement in Germany obviously could be viewed as spilling over in countries in Europe.

We don’t see that at this point. There is always a pressure discussions from various countries based on the mix of activities in the MS space, but right now other than German announcement we don’t see a major impact there coming this year.

The growth, again it varies from country to country so much, but we certainly see growth based on our ability to expand our reach in the country that we currently are moderately engaged in or accruing patients and so we see that as a real opportunity going forward.

As you calculate and correct the PML risk with TYSABRI, how do you account for patients, who are on drug holiday? Do you just treat them as other on drug or do you adjust your calculations to reflect that some (inaudible) therapy?

Hi, this is Rick again. We count the total number of infuse that’s our current metric for doing that.

Good question. Lot of debate over that one but that’s our current metric.

All right. Thanks for taking the question.

Maybe I am just a little bit confused when you talk about drug suspensions versus drug discontinuations. For TYSABRI, I think I caught both of this in terms of phrase in the earlier discussion and I am just wondering, how does the definition differ between the two?

In the United States, where all TYSABRI treated patients are entered into the TOUCH program, the division has the opportunity to re-begin therapy at any time. So in a way it’s a bit difficult for us to determine the difference between a drug suspension and a drug discontinuation.

However, those kinds of statistics can only be had when we look at the TOUCH program going forward. We have incomplete data on that.

I just have a question on the AVONEX patents. Just any updates you can provide on whether you have got any meaningful discussions and when we could see potential agreements signed as they relate to that intellectual property?

Yeah, this is Paul. Nothing to report actually at this point in time and we will try to keep you informed along the way as soon as we do have something to report.

Thanks. I am just wondering, what's a realistic timeline for completion of STRATIFY 2 and is there any interim analysis STRATIFY 2 focused on JCV prevalence that could augment the data, from STRATIFY 1.

STRATIFY 2 is intended to go out for two year. It will depend a little bit upon enrollment and I at this point, the (power) calculations are gone and we generally don’t share that kind of information.

However, we do really feel that on the study of (power) is to achieve this desired results at about 8,000 patients for two years.

Just I wanted to circle back on the, I think the stock buyback mentioned it, Paul you mentioned that you will look to identify this and take advantage of excess cash. Can you may be give a range of where you feel are the optimum, net cash level would be, and what threshold do you have excess cash?

A good question. I mean it is something we debate for years and I hate to using optimal compatible structure.

You really can't look at in a vacuum, because it is so tied to the business development and corporate development plans that you have underway. We have, I mean, I did want to just going to emphasize that we certainly love this business.

We think there is great returns in this business and we continue to look for business development and corporate development opportunities, but what we are influenced by is that, that can come over the last number of years, you have seen that come in business development opportunities with a relatively modest use of capital in terms of adding value and bringing in-licensing collaborations in business development opportunities into the pipeline. We will look at larger usage as every company in our space does and we’ll also kind of tie that up vis-a-vis are the credit markets in the financing capacity that is available to which I think at this point in time we’d call it as more favorable than a year ago.

So I think it still a balance approach but should there be access capital in the business which we've largely concluded very recently? We will look to return it to shareholders in the most efficient manner.

Thank you.

I have a question with regard to the 190 per week patient adds, so lets phase out March average. Can you provide more?

Is that higher at the end of March and the beginning of March or is too early to have a real number for that?

I actually don’t have it, it may have discerned on the four-week basis within March. I don’t think its materially different week-to-week-to-week in March.

Even if it was I don’t know if that’s incredibly telling I think the broader trend that we’ve seen in the business is that subsequent to the label discussions and there is a lagged affect here because patients and physicians decide, then it takes four to five or six weeks to put them on therapy and get their first infusion. So subsequent to those discussions that were happening in the fourth quarter, we did see a modest slowdown in net patient adds on a gross basis as well.

We’ve seen that largely pick-up and that kind of trends back into the four to five weeks since the label discussions were largely finished. I think I'd just kind of keep it at full month of March basis.

Because for the quarter is about 120, I'm just wondering, so these new patient adds really is now either going down or going up gradually. They really kind of drop or rise pretty significantly.

Can you explain that why one month could be so different than the months before or the month after?

We think it's owing to physicians digesting new information, and most meaningful information was the label discussions in the backend of the year. We largely passed that and we're feeling a little bit heartened by the trajectory that we are seeing in March.

Thanks for the follow-up. It's Nick again, for Jim.

I'm interested in your thoughts on primary infection for JCV, while patients are taking TYSABRI, and my concerns are driven by the pre-clinical SV40 data, which are worrying, and as you SV40 has 67% homology to JCV, so perhaps not a perfect model. I think you quoted 2% per annum primary conversion rate to JCV positivity.

I'm wondering what your level of confidence of this because the published data comparing JCV [allies] to say it more elegant piece. That assay suggest that they allies underestimates the true exposure, previous exposure to the JC virus.

So how confident are you in that 2% primary conversion number?

Hey Nick, this is Jim. We decided to jump all on that question and we appointed the least qualified person to answer and that became me.

I’ll let Rick or Evan to add in to it, but the data we have in the primary section is not only the data we have seen from our own collections of samples over a couple year periods time but what else is out there in the literature and it appears to be in the range of 1% per year. Maybe I will let Evan and Rick maybe add on to that a little bit of color.

This is Evan. Obviously the assays and other things in use are really important in determining of this.

When we first started looking in to PML several years ago there were numbers all over the place so that the incidence of latency or prior exposure to JC virus. I mean we think that we have gotten better assays and we believe that our data and the program that we have going forward will give better answers to that question.

At the moment, the 1% to 2% we think is pretty reasonable. I don’t think that, you describe maybe more sensitive techniques or other things.

I just don’t think that numbers going to be wildly off. Two a point words really going to matter whether its 1.2 or 2.3, I think we are in the range and the program we have going forward will help us better define that.

Obviously, we think that is something important and as we put this program together going forward to help stratify risks of our patients and physicians. Obviously the new conversion rate that happens, whatever that is, is going to be an element of the pieces of information that we need use to review and monitor to make good decisions.

So we have an interest in trying to get that right overtime.

So can I just ask any other 30 or so cases of PML, do you have any baseline data that you can go back to, so I'll try and ask that question if primary conversion connotes a higher risk for developing PML?

Yeah, through the data that we have given you, those 13 cases represent to date, the patient base that we have with the right data to be able to go back and ask those questions. If we had more, we would be sharing more.

We would like to get the numbers up as well. So as new cases come up, sometimes there is that opportunity, but that’s probably where most of those cases are going to come from, new members would come from.