September 26, 2012
Vertex Pharmaceuticals announced the discontinuation of work on the experimental hepatitis C drug ALS-2158 and resumption of development on another hepatitis C drug, ALS-2200. ALS-2158, which was being developed with partner Alios BioPharma Inc., did not show enough efficacy. On the other hand, ALS2200 showed promise in an early trial. The company is planning a mid-stage or Phase II trial of ALS-2200 in combination with ribavirin and one trial to evaluate ALS-220 in combination with the existing drug Incivek. Incivek, which must be taken with interferon, was approved in 2011 and so far has doubled the cure rate of prior standard treatments.
Vertex acquired worldwide rights to ALS-2200 in a licensing agreement with Alios in June 2011. According to the company, the drug is designed to inhibit replication of the hepatitis C virus and the virus does not seem to become easily resistant to it. ALS-2200 is a nucleotide analogue or nuc, a class of drugs that has had problems with safety concerns.
Vertex is competing with other pharmaceutical companies including Gilead Sciences, Inc., and Abbott Laboratories to bring to market a hepatitis C drug that is not taken in combination with interferon, as interferon causes flu-like symptoms and may make patients discontinue treatment. For these reasons, the company is being tight-lipped about the structure of ALS-2200. However, more details are expected at a medical conference in November.