NEW YORK – Nouscom said on Tuesday it has dosed the first patient in a Phase Ib trial of its neoantigen cancer vaccine, NOUS-PEV, plus pembrolizumab (Merck’s Keytruda) in patients with advanced melanoma and non-small cell lung cancer.

The trial is evaluating the combination as a first-line treatment in up to 34 patients with unresectable stage III or IV cutaneous melanoma and PD-L1-positive stage IV NSCLC. Lung cancer patients must express PD-L1 in at least 50 percent of their tumor cells to enroll in the trial.

Trial investigators will evaluate the safety profile, anti-tumor activity, and immunogenicity of NOUS-PEV plus pembrolizumab. Stefan Symeonides, an oncologist and researcher at the University of Edinburgh and an investigator in the trial, is expecting preliminary results to be available next year.

“There is still a significant unmet medical need for new therapeutics to overcome tumor resistance to anti-PD1 immunotherapies,” Symeonides said in a statement. “Vaccination, and especially personalized vaccination, has huge potential, and Nouscom’s innovative technology has unique features that are promising for a best-in-class platform.”

The NOUS-PEV vaccine is personalized to each patient based on the unique mutations or neoantigens that are most likely to spur an immune response against the tumor. In the trial, researchers will obtain samples from each participant’s tumor for next-generation sequencing to identify mutations. Then, those specific neoantigens will be encoded into Nouscom’s heterologous prime boost platform and its proprietary algorithm, VENUS, will select up to 60 of the most immunogenic neoantigens for the development of the personalized vaccine.