Moderna, Merck say vaccine improved survival in patients with deadly skin cancer

The shot is a key part of Moderna’s pipeline that has helped shore up investor sentiment for the biotech company following a rocky last year, when demand plummeted for its Covid vaccine, for now its only commercially available product.

The data includes the initial results the two companies announced in December.

Among new data, nearly 75% of patients who took the combination were alive without any signs or symptoms of their cancer returning at the 2½-year mark. That compares with 55.6% of patients who got Keytruda alone. 

That benefit was observed across different subgroups of patients, regardless of whether they had tumors with a large number of mutations or whether they had enough of a protein — called PD-L1 — that helps keep the body’s immune responses in check. 

The data reflects the potential for the shot to help treat a “broad range” of melanoma patients, Dr. Kyle Holen, Moderna’s head of development, therapeutics and oncology, said in a release.

The overall survival rate of patients who took the vaccine in combination with Keytruda was 96% after 2½ years. That compares with 90.2% among those who took Keytruda alone.

As the companies previously announced, patients with severe forms of the cancer, known as melanoma, who received the combination were 49% less likely to die or have their cancer return than those who took Keytruda alone after roughly three years. The combination also slashed the risk of melanoma spreading to other parts of the body, or death, by 62%.

The most common side effects associated with the vaccine were fatigue, injection site pain and chills, according to the data. The majority of those side effects were mild. Patients who received the combination had slightly higher immune-related side effects.

The vaccine, which uses the same mRNA technology as Moderna’s Covid vaccine, is custom-built based on an analysis of a patient’s tumors after surgical removal. The shot is designed to train the immune system to recognize and attack specific mutations in cancer cells. 

Moderna is excited about working to reduce the time between the initial analysis of a tumor and when a patient gets injected with the shot, CEO Stephane Bancel said in an interview with CNBC.

Meanwhile, Merck’s Keytruda, which is approved to treat melanoma and other cancers, belongs to a class of widely used immunotherapies designed to disable a certain protein that helps cancer evade the immune system.

The U.S. Food and Drug Administration in February gave breakthrough therapy designation to the cancer vaccine for the treatment of melanoma. That designation aims to speed up the development and review of treatments for serious and life-threatening diseases.

But Moderna also plans to file for accelerated approval with the FDA, Bancel noted. The process allows for expedited approvals of drugs for serious conditions that fill an unmet medical need.

Melanoma is responsible for the large majority of skin cancer deaths, according to the American Cancer Society. The rate of melanoma has increased rapidly over the past few decades, according to the organization.

About 100,000 people will be diagnosed with melanoma in the U.S. this year and nearly 8,000 people are expected to die from the disease, according to the American Cancer Society.

The two drugmakers are studying the combination as a treatment for late-stage melanoma in a phase-three trial, which began in July. Bancel said the progress of that trial is “ahead of our plans” so far. 

Moderna is also conducting another phase three trial of the vaccine in patients with a type of lung cancer. 

This year, Merck and Moderna started a two-part mid- to late-stage trial on the vaccine and Keytruda in patients at an advanced stage of a common skin cancer. The companies are also conducting a phase two trial in certain patients with a type of kidney cancer, and another study on people with a type of bladder cancer.