Merck, Seagen Drug Combo Seen as New Bladder Cancer Standard

Merck & Co. and Seagen Inc.’s drug cocktail is set to replace chemotherapy as a top choice for bladder cancer patients, doctors said, the first alternative to the toxic treatment in 30 years.

(Bloomberg) — Merck & Co. and Seagen Inc.’s drug cocktail is set to replace chemotherapy as a top choice for bladder cancer patients, doctors said, the first alternative to the toxic treatment in 30 years.

The combination, developed with Astellas Pharma Inc., helped patients live nearly twice as long — an average of 31.5 months — as those who got chemotherapy alone, in a large study presented on Sunday at the European Society for Medical Oncology’s annual meeting. 

The results appeared alongside a Bristol-Myers Squibb Co. combination of immune therapy Opdivo and chemotherapy, which also boosted survival rates more than chemotherapy alone — but not as much as the chemo-free regimen. 

The chemo-free results are “very impressive,” said Andrea Apolo, chief of the Bladder Cancer Section in the Genitourinary Malignancies Branch at the National Cancer Institute’s Center for Cancer Research, who reviewed the results and wasn’t involved in the study. “I think it will become the standard of care for bladder cancer.” 

The drug cocktail combines immune therapy Keytruda with Padcev, a new type of medicine called an antibody drug conjugate. It’s designed to zap cell-killing therapy just to the parts of the body that need it the most, helping to mitigate some of the side effects of treatment. The technology is 200 times more powerful than traditional chemotherapy, Apolo said.

The data “probably means that some percentage of these patients will never have the disease come back,” Seagen Chief Executive Officer David Epstein said in an interview, adding that more time is needed to show that definitively. “Some people now have the hope of living a relatively normal life even though they’ve been diagnosed with bladder cancer, and for the bulk of people they’re going to have at least a few years, which is a lot different than what it was before.”

Read more: Seagen Rises on Positive Bladder Cancer Study with Merck

The partners will seek US regulatory approval for the new combination this year for first-line metastatic bladder cancer patients, Epstein said. The FDA cleared it earlier this year for those who can’t take a certain type of chemotherapy. 

Doctors cheered during the conference presentation, normally a buttoned-up affair, when study lead Thomas Powles, director of Barts Cancer Centre, said the new combination beat chemotherapy. “This is the first time,” Powles told attendees. There are about 15,000 cases per year in the US that would benefit from the drug combination, he said in a separate interview.

Before the latest generation of drugs that harness the immune system against tumors, doctors found it difficult to recruit bladder cancer patients into clinical trials at all, said Matthew Galsky, co-director of the Center of Excellence for Bladder Cancer at the Tisch Cancer Institute, a part of Mount Sinai.

And when new immune therapies emerged, they disappointed in bladder cancer trials, Galsky said. This new study isn’t just revolutionary for these patients, it’s one of the first large studies that shows immunotherapy and antibody drug conjugates beating chemotherapy in solid tumors, he said.

Higher Cost

Doctors said one question will now become what to use after patients who’ve taken the new combination relapse. More studies will need to be done to assess which patients may grow resistant to the therapy, said Toni Choueiri, director of the Lank Center for Genitourinary Oncology at Dana-Farber Cancer Institute.

Cost will also be a factor, said the NCI’s Apolo. The Merck-Seagen-Astellas cocktail costs about $45,000 per three-week treatment cycle, compared with about $400 per treatment cycle for chemotherapy, according to the Journal of Clinical Oncology. 

List prices aren’t an accurate representation of what most purchasers and patients pay, Seagen said. 

Pfizer Inc. agreed to buy Seagen for $43 billion earlier this year on the strength of its portfolio of antibody-drug conjugates. 

Read more: Pfizer’s $43 Billion Seagen Deal Wins Unconditional EU Nod

(Updates with Seagen CEO in sixth paragraph, details throughout)

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