ADC Reviews

Merck drops oncolytic virus therapy Cavatak (V937)


On October 27, Merck announced its third-quarter financial report, and its product pipeline no longer includes the oncolytic virus therapy Cavatak (V937) obtained from the acquisition of Viralytics in 2018. On the same day, Merck confirmed to the media Fierce Biotech that it had stopped research and development plans for Cavatak (V937).

Merck & Co. ditches oncolytic virus Cavatak 4 years after buying Viralytics

Merck & Co. is bidding adieu to the oncolytic virus acquired from its 2018 purchase of Viralytics, with the pipeline change disclosed weeks after the Big Pharma hitched its wagon onto Moderna’s cancer vaccine program.

A spokesperson for Merck confirmed to Fierce Biotech this morning that it discontinued the program “as part of our routine pipeline prioritization.” Merck’s updated pipeline, outlined in a third-quarter earnings presentation (PDF), no longer included V937, also known as Cavatak, to treat a range of cancers.

In 2018, Merck acquired Viralytics, an Australian-listed company focused on developing oncolytic immunotherapies for cancer, for $394 million. In addition, Merck acquired full rights to Viralytics’ investigational oncolytic immunotherapy Cavatak. Cavatak is a proprietary formulation (available as an intratumoral and intravenous formulation) against a specific oncolytic virus (coxsackievirus type A21) that has been shown to selectively infect and kill cancer cells.

Previously, Merck has used Cavatak in multiple clinical trials, including in combination with Merck’s anti-PD-1 therapy Keytruda, for melanoma, prostate cancer, lung cancer and bladder cancer. Several clinical trials are still ongoing for Cavatak in combination with Keytruda.

In August 2021, Merck announced the results of a Phase II trial of Cavatak monotherapy in patients with Phase 3 or 4 unresectable melanoma. The study showed that among the 57 patients included, Cavatak monotherapy had a progression-free survival rate of 38.6% at 6 months, which decreased to 32.9% at 12 months, and overall survival at 12 months. The rate was 75.4%.

It’s unclear what ultimately influenced Merck’s downgrade of the oncolytic immunotherapy Cavatak. But recent trends suggest that Merck is well-positioned in terms of cooperation. Just a few weeks ago, Merck paid Moderna $250 million to advance the co-development and commercialization of the Personalized Cancer Vaccine (PCV) mRNA-4157/V940. Currently, mRNA-4157/V940 is being used in combination with Merck’s PD-1 antibody Keytruda to treat patients with intermediate and high-risk melanoma.