Merck pairs PD-1 powerhouse Keytruda with Genexine vax to fight HPV-based cancers

Years after two late-stage cancer vaccine failures put the field’s future in question, leading companies still believe they can amp up combo regimens. Now, Merck is partnering its key immunotherapy Keytruda with a Genexine vax to battle cervical cancer.

Merck will test its cancer-fighting checkpoint inhibitor Keytruda in combo with the biotech’s cancer vaccine, GX-188E, in HPV-induced cancers. They’ll start with a Phase Ib/IIa trial, with an option to expand the collaboration into Phase III registration studies in the indication.

It's the latest team-up between a checkpoint inhibitor and a cancer vaccine as Big Pharma puts its R&D machine behind the approach. South Korea-based Genexine in a statement said it believes Keytruda can complement its vaccine to improve on the 12.5% response rate the Merck drug posted alone in advanced cervical squamous cell cancer.

The pair will start the trial in the first half of 2017 in up to 40 patients. Genexine is currently developing its vaccine in Phase II trials in cervical intraepithelial neoplasia and in Phase I for HPV cancers.

The partnership joins a stream of collaborations after late-stage cancer vax failures by Merck KGaA and GlaxoSmithKline left a cloud on the field. Looking for a path forward in 2014, Johan Vansteenkiste of Belgium University Hospitals Leuven said that such combos could be of “major interest.”

Those words continue to ring true as leading biopharmas including Bristol-Myers Squibb and AstraZeneca have partnered their checkpoint inhibitors with cancer vaccines from smaller biotechs Bavarian Nordic and Inovio, respectively. For the biotechs, success could mean big payoffs approaching $1 billion.

Johnson & Johnson, for its part, has partnered with GVAX developer Aduro in a collaboration potentially worth $817 million.