One of Boehringer Ingelheim’s pipeline drugs has achieved high response rates in patients with chronic genotype-1 hepatitis C virus (HCV) in Asia who have not been treated before.

Eighty-eight per cent of this patient group who received faldaprevir+ plus pegylated interferon and ribavirin (PegIFN/RBV) achieved viral cure, according to a new, post-hoc sub-analysis of the Phase III STARTVerso 1 and 2 trials.

The geography is significant since rates of HCV infection in Asian countries are particularly high: the patient sample was 243 patients from Japan, Korea and Taiwan.

Hepatitis C, a leading cause of chronic liver disease, affects around 170 million people worldwide and many patients remain undiagnosed until they have liver disease itself.

Data released during the APASL Liver Week in Singapore found that 172 out of 196 patients treated with faldaprevir+ 120mg or 240mg added to PegIFN/RBV achieved viral cure compared with 62% (29 out of 47) who received placebo plus PegIFN/RBV.

Primary endpoint - viral cure 12 weeks after treatment finished - was achieved with every patient in Taiwan, 86% of those in Korea and 85% of patients in Japan in the faldaprevir+ arm.

“The results are particularly relevant given that HCV presents a huge health burden in Asia,” said Professor Masao Omata, lead author of the sub-analysis. “The viral cure rates of close to 90% in patients infected with the difficult-to-cure genotype-1 HCV highlight the potential of faldaprevir+ to address this unmet medical need.”

The trials suggest other benefits for patients, too, with the vast majority - 95% taking the 120mg dose and 93% on 240mg - able to shorten their treatment to 24 weeks because their virus levels were low at week 4 and week 8.

Of these, 91% (120mg) and 92% (240mg) achieved viral cure and both doses were shown to be well-tolerated.

“Addressing the diversity of HCV patients worldwide is essential to drug development and individualised patient management in this field,” said Klaus Dugi, Boehringer’s senior vice president, medicine.

Wider figures from STARTVerso 1, presented in April, showed that up to 80% of patients from Europe and Japan treated with faldaprevir+ and PegIFN/RBV achieved viral cure compared with 52% in the placebo arm.

Data from STARTVerso 2 (which includes patients from the US and Canada as well as Taiwan and Korea) plus STARTVerso 3 and 4 (looking at treatment-experienced patients as well as those who have both HIV and HCV) are expected later this year and in 2014.

HCV is a fertile area of research with a high profile: two new hepatitis C drugs, Janssen’s Incivo (telaprevir) and MSD’s Victrelis (boceprevir), were awarded the 2012 UK Prix Galien prize.

Existing injectable interferon treatments include Roche’s Pegasys and Merck’s PegIntron.