Biotech Values

[DewDiligence]

IDIX – This article has the only discussion of the IDX899 deal I’ve seen
that asks (but does not answer) the question I asked in the prologue of
#msg-35391933: How will GSK integrate IDX899 into a marketing
strategy for the HIV market? GSK’s two HIV combo pills—Epzicom
and Combivir—are essentially obsolete products. Co-formulating IDX899
with Epzicom or Combivir won’t make either or them capable of competing
with Atripla. Comments appreciated.

http://www.pipelinereview.com/content/view/25201/309/

›GSK Renews HIV Pipeline

15-Feb-2009

GlaxoSmithKline and Idenix are to co-develop IDX899 for the treatment of HIV infection. Despite having eight marketed HIV products, GSK lost its position as market leader to Gilead in 2007. The new collaboration with Idenix will, however, help the company to maintain its share in the fiercely competitive HIV market.

Idenix Pharmaceuticals, Inc and GlaxoSmithKline (GSK) have entered into a license agreement, granting GSK exclusive worldwide rights to IDX899. Under the terms of the agreement, GSK will assume all development responsibility and associated costs for IDX899, while Idenix will receive an upfront payment of $34 million and will be eligible to receive up to $416 million in development, regulatory and sales milestones. Furthermore, if IDX899 is successfully developed and commercialized, Idenix will receive double-digit, tiered worldwide royalties.

IDX899 is a novel non-nucleoside reverse transcriptase inhibitor (NNRTI) in Phase II trials for the treatment of HIV/AIDS. While NNRTIs are a popular choice for first line therapies, they are prone to resistance and Sustiva, the class leader, is associated with central nervous system-related side effects. Studies to date have shown that IDX899 has high potency with low milligram doses, activity against NNRTI resistant strains and once-daily administration. The possibility of once-daily dosing with IDX899 offers the opportunity for co-formulation with GSK's nucleoside reverse transcriptase inhibitors (NRTIs).

Currently, GSK is marketing its leading [???] NRTI fixed dose combination of abacavir and lamivudine under the brand name Epzicom. Adding IDX899 as a third component would provide the company with a triple combination similar to Gilead's and Bristol Myers Squibb's Atripla. However, GSK is currently facing setbacks with Epzicom: the drug is already associated with a hypersensitivity reaction, and data from the ACTG 5202 study have shown higher rates of biologic failure in Epzicom patients with high viral loads. Additional data from the Data Collection on Adverse Events of Anti-HIV Drugs (DAD) cohort and the SMART study suggest an increased risk of myocardial infarction associated with use of abacavir. This decreases the attractiveness of a triple combination including IDX899 and Epzicom [no kidding!]

Gilead replaced GSK as market leader in the HIV segment in 2007. GSK has eight marketed products, but many of its brands are relatively old and face patent expiration. In addition, several late-stage R&D setbacks over the past two years have left the company bereft of any HIV compounds in active clinical development. Consequently, the in-licensing of IDX899 provides a much-needed pipeline boost. While the collaboration with Idenix may not be sufficient to restore the company's leading position, Datamonitor believes that it could help GSK to maintain its share in a market which is becoming fiercely competitive.‹