Yestoday, Achillion Pharmaceuticals (NASDAQ: ACHN) announced positive interim results from Phase II study of second-generation NS5A inhibitor ACH-3102 and Phase I study of NS5B polymerase inhibitor ACH-3422. ACH-3102 plus sofosbuvir cured hepatitis C patients after only 6 weeks of treatment which is much shorter than 12 weeks of the currently approved treatment.
Achillion looks forward to developing its own in-house best-in-disease combo, ACH-3422 plus ACH-3102. However, both sofosbuvir and MK-3682 (IDX21437) are more potent than ACH-3422. In GT1 patients, 700 mg of ACH-3422 demonstrated 3.4-log mean maximal reduction in viral load at seven days, whereas 300 mg of MK-3682 achieved 4.8, 3.9-log mean maximal reduction in GT1a, GT1b patients, respectively.
In June 2014, Merck acquired Idenix Pharmaceuticals (NASDAQ:IDIX) for $3.85 billion and obtained MK-3682. Merck and not Achillion is more likely to develop a best-in-disease combo. In any case, it is not easy to demonstrate significant superiority over Gilead Sciences’ Sovaldi/Harvoni.
On the other hand, newly diagnosed cases with hepatitis C are relatively limited. It is a prevalence market with no future. Big Pharmas are competing to win market share before the market disappears.
Gilead set the price of Sovaldi and Harvoni at $84000 and $94500, respectively, while AbbVie set the price of Viekira Pak at $83300. Just yesterday, Express Scripts, the largest prescription management company, announced that it has struck a multi-year deal with AbbVie, making Viekira Pak the exclusive option for GT1 patients. The negotiated price for Viekira Pak was not disclosed, undoubtedly, AbbVie offers a further discount. Shares of Gilead fell over 14% yestoday.
Viekira Pak contains ombitasvir, paritaprevir and ritonavir tablets co-packaged with dasabuvir tablets. The recommended dosing for Viekira Pak is two ombitasvir/paritaprevir/ritonavir tablets once daily and one dasabuvir tablet twice daily. For patients whose liver is unable to function properly, two more tablets of ribavirin is recommended. Gilead’s Harvoni is much more convenient. Patients treated with Harvoni just take a single tablet once daily. The Express Scripts deal is limiting patients’ treatment options.