Global Insight Perspective | |
Significance | Biotech partners Biogen Idec and Elan Corp. have announced that the U.S. FDA has approved the companies’ supplemental Biologics License Application (sBLA) seeking to reintroduce the MS treatment Tysabri onto the U.S. market. |
Implications | Although the return of Tysabri represents a success for the two biotechs, considerable limitations have been placed both on the drug’s indicated use and on its distribution. |
Outlook | While demand from MS patients, who believe the benefits of the drug significantly outweigh its risks, is likely to be high, the limitations imposed have already led many investors to move projected sales downwards. |
Biogen Idec and Elan Corp. announced yesterday that the U.S. FDA has approved the companies’ supplemental Biologics License Application (sBLA) seeking to reintroduce Tysabri onto the U.S. market. Tysabri is a monoclonal antibody used to treat patients with relapsing forms of MS. It slows the progression of the disability and reduces the frequency of clinical relapses. However, the regulatory agencies’ approval imposes significant limitations on Tysabri’s indicated use. Firstly, due to the safety issues that still surround this product, the biotechs will only be able to supply Tysabri under a special restricted distribution programme. Secondly the drug is only indicated for use as a monotherapy, meaning that it cannot be used in combination with other drugs that modify the immune system. Finally, it is only indicated for patients who have not responded adequately to, or who cannot tolerate, other MS treatments.
Tysabri was initially approved by the FDA back in November 2004. At the time, the drug appeared to offer new hope to MS patients and was widely touted as a potential blockbuster for Biogen and Elan. However, these hopes dissipated in February 2005, when Biogen and Elan suddenly withdrew the product from the market. This was prompted by reports of three cases of the rare and potentially fatal viral infection of the brain, Progressive multifocal leukoencephalopathy (PML), among MS patients using Tysabri. Despite this considerable setback, Biogen and Elan have worked to return Tysabri to the market, carrying out a number of safety evaluations and finally submitting a sBLA for reintroducing the drug in September 2005.
According to Reuters, FDA officials claim still to know very little about how to predict, prevent or treat PML. As a result, it consulted in March 2006 with its Peripheral and Central Nervous System Drugs Advisory Committee on how to reduce the risks posed by PML while still making Tysabri available to MS patients. The committee recommended that a risk-management plan be put in place to try to minimize the chances of patients contracting PML and to try and identify the reasons behind any infection. In accordance with this, Biogen-Idec developed the TOUCH (Tysabri Outreach: Unified Commitment to Health) prescribing programe to facilitate appropriate use of the drug. The main features of this programme are:
- Tysabri will carry revised labelling that specifically warns of the risk of PML. It will also carry strongly worded warnings against the concurrent use of Tysabri with other immune-system modifying drugs, since the three previously confirmed cases of PML linked to Tysabri’s use were all patients who had been concomitantly exposed to immunomodulators or immunosuppressants;
- The TOUCH programme will require the mandatory enrolment of all prescribers, central pharmacies, infusion centres and patients involved in the administration of Tysabri;
- Tysabri will only be distributed to infusion centres authorised under the TORCH plan;
- Prior to beginning Tysabri therapy, patients will undergo a Magnetic Resonance Imaging (MRI) scan to help to differentiate future advancements in MS from potential signs of PML;
- The TOUCH programme will ensure that patients and physicians have access to FDA-approved educational tools; and
- The TOUCH plan will continuously assess PML risk and the overall safety of Tysabri through a 5,000 patient observational study over five years.
Following yesterday’s decision by the FDA, Biogen has to complete certain key activities relating to the introduction of the TORCH risk management programme. As a result of this delay, the company anticipates that it will be able to make Tysabri available to eligible MS patients in July.
Outlook and Implications
Although the FDA’s approval for Tysabri will be viewed by the two companies as a vindication of their continued efforts to bring the drug back to the U.S. market, the significant limitations placed on the drug’s indicated use means that it does not represent the strong positive they had hoped for. Biogen’s share price fell yesterday after this announcement, as investors analysed the likely impact that these restrictions would have on sales of Tysabri. The TORCH programme will considerably increase the cost of Tysabri sales, and the fact that Tysabri is only indicated for patients who have tried other MS treatments first considerably limits the potential future value of the drug.
These restrictions, which look set to significantly dampen sales of Tysabri, are likely to prove a greater problem for Elan than Biogen. Elan is more dependent on Tysabri sales to improve its operating outlook, whereas Biogen already has a number of blockbuster drugs within its portfolio, including the market-leading MS treatment Avonex (interferon beta-1a), which generated US$1.5 billion in sales last year.
Related Articles:
- United States: 1 June 2006:Biogen Idec to Acquire Fumapharm, Gains Greater Control Over Development of New MS Drug
- United States: 10 April 2006: Biogen, Elan Report Tysabri's Quality of Life Benefits
- United States: 30 March 2006: United States: Biogen Idec, Elan Restart Tysabri MS Trials
- United States: 22 March 2006: United States: FDA Extends Tysabri Review
- Ireland: 9 August 2005:Elan, Biogen Find No New PML Cases in Tysabri Safety Study