The Phase II trial was looking at the effect of Lynparza in combination with abiraterone (A.K.A Zytiga) in patients with metastatic castration-resistant prostate cancer (mCRPC) – a type of prostate cancer which keeps growing despite testosterone levels being reduced to very low levels.
The data showed that median radiologic progression-free survival (rPFS) – the length of time a patient lives with the disease without it getting worse – was 13.8 months in the combination arm compared to 8.2 months with abiraterone alone.
Over the long run, though, the combination therapy wasn’t much more effective in keeping patients alive for longer.
Median overall survival was 22.7 months in those taking both Lynparza and abiraterone versus 8.2 months in patients just taking the latter.
“There is a significant unmet medical need for patients with metastatic castration-resistant prostate cancer as they are a high-risk group with limited treatment options,” noted Merck’s chief medical officer Roy Baynes.
“Lynparza is the first PARP inhibitor to demonstrate activity in combination with standard-of-care treatment in prostate cancer,” noted Roy Baynes, senior vice president and head of Global Clinical Development, chief medical officer, MSD Research Laboratories.
AstraZeneca shares were broadly flat at £54.17 in early afternoon trading in London, while Merck’s stock was also unmoved in the pre-market in New York at US$62.02.