The Food and Drug Administration granted Merck a priority review for its application for Keytruda in combination with concurrent chemoradiotherapy, the company announced Wednesday.

According to Merck, the FDA based its decision on the KEYNOTE-A18 trial, which showed that Keytruda in addition to concurrent chemoradiotherapy was beneficial for patients with high-risk locally advanced cervical cancer. The results showed it boosted progression-free survival compared to concurrent chemoradiotherapy alone.

Keytruda currently has two approved indications in cervical cancer. If the latest application is approved, it would be the first indication for Keytruda in an earlier form of the disease.

The use of Keytruda in combination with chemoradiotherapy provides a valuable tool in treating advanced cervical cancer, an area that has lacked for new therapies in recent years, according to Gursel Aktan, VP of global clinical development at Merck Research Laboratories.

Aktan added that Merck would be working closely with the FDA to bring Keytruda to patients in need of additional treatment options.

“The standard of care for patients with locally advanced cervical cancer has not changed in more than two decades, and the majority of patients will experience recurrence or progression of their disease,” Aktan said. “If approved, Keytruda will be the first immunotherapy available for patients with newly diagnosed high-risk locally advanced cervical cancer.”

The priority review is another notable development for Keytruda, which was originally approved by the FDA in 2014. 

Since then, it’s been approved for a variety of cancer indications, including melanoma, non-small cell lung cancer, gastric cancer and cervical cancer.

The immunotherapy has long been considered a blockbuster for Merck, bringing in more than $42 billion between 2019 and 2021 — and $20.9 billion last year. 

Keytruda will outpace all Rx brands by global sales in 2028, according to a five-year World Preview recently published by Evaluate. 

However, with its patent protection set to expire in 2028, the pharma giant has sought to expand Keytruda’s reach to other indications, often as a combination therapy.

The company has collaborated with Moderna on an mRNA cancer vaccine that could treat patients in combination with Keytruda. The two companies launched a Phase 3 trial for the effort in July. 

Still, drug pricing regulation remains one of the top healthcare priorities in the current Congress and Merck’s movement around Keytruda has drawn the ire of a leading progressive lawmaker. 

In February, Sen. Elizabeth Warren, (D-Mass.), wrote a letter to the U.S. Patent and Trademark Office (PTO) calling for scrutiny over Merck’s attempts to extend Keytruda’s patent protection.

In a statement at the time, Merck noted that it was “continuously innovating to enhance the benefits of Keytruda in order to reach greater numbers of patients and to increase efficacy and convenience of the treatment,” and that it “protects this additional innovation through the filing of patent applications.”

Over the summer, Merck sued the federal government over the Inflation Reduction Act provision that allows Medicare to negotiate the prices of certain Part D drugs. The company was joined by other Big Pharma rivals in taking legal action.