April 16 (Reuters) – An experimental mRNA cancer vaccine developed by Moderna Inc (MRNA.O) and Merck & Co (MRK.N) reduced the risk of death or recurrence from the deadliest skin cancer by 44% compared to Merck Keytruda’s immunotherapy. Alone, US researchers reported at a medical meeting on Sunday.
The findings suggest that adding a specific cancer vaccine based on mRNA technology to Keytruda, which increases the immune response, could extend the time patients spend without recurrence or death, said Dr. Jeffrey Weber of New York University’s Langone-Perlmutter Cancer Center, who provided the findings. .
“From a general cancer treatment standpoint, this is a huge potential breakthrough,” Dr. Ryan Sullivan, a skin cancer expert at Mass General Cancer who worked on the study, said in a statement.
The findings, presented at the American Association for Cancer Research meeting in Orlando, Fla., add data detail to partial results the companies released in December. Additional data will be presented at an upcoming clinical meeting and published in a peer-reviewed journal.
The combination therapy has won US Advanced Therapy and the European Medicines Agency’s PRIME Scheme designation, regulatory programs aimed at accelerating the development of innovative therapies.
The Merck/Moderna collaboration is one of many that combine powerful drugs that unleash the immune system to target cancers with mRNA vaccine technology. BioNTech SE (22UAy.DE) and Gritstone Bio Inc (GRTS.O) are working on competing cancer vaccines based on mRNA technology.
The vaccine is custom built based on analysis of the patient’s tumors after surgical removal. Vaccines are designed to train the immune system to recognize and attack specific mutations in cancer cells.
Merck’s Keytruda, which is approved to treat melanoma and many other cancers, belongs to a class of widely used immunotherapies known as checkpoint inhibitors that are designed to disable the PD-1 protein, or programmed death 1, that helps cancer evade the immune system.
A mid-stage trial enrolled men and women at high risk of developing skin cancer.
Of the 107 study subjects who received the experimental vaccine, mRNA-4157/V940, and Keytruda, cancer returned in 24 people (22.4%) within two years of follow-up, compared to 20 of 50 (40%) who received Keytruda alone.
There was little difference in response rates between people whose tumors had lots of mutations — a typical indicator of response to immunotherapy — and those whose tumors did not.
The scientists stated that severe side effects were similar between the two arms of the study. Fatigue was the most common side effect reported by patients specifically related to the vaccine.
Merck said the two companies are in talks with US regulators about designing a late-stage trial, which will likely be required for approval of the collection system.
Eliav Bar, global chief of clinical development and chief medical officer at Merck, said in an interview that it may take three or four years before results from larger trials are known.
It took about eight weeks, Barr said, to design a personalized mRNA vaccine for each patient.
In the past, similar experimental cancer vaccines targeting a single tumor mutation, or neoantigen, have been developed.
Moderna’s mRNA technology allowed up to 34 new elements to be included, which Barr called “amazing”.
Currently, scientists cannot predict which single mutation is important in generating an anti-tumor response. By using mRNA technology in conjunction with Keytruda, “we can create this shotgun approach … that can create a more robust immune response,” Barr said.
(Reporting by Julie Stenhuisen in Chicago and Michael Ehrman in New York.) Edited by Bill Berkrot
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