Merck & Co.'s hot experimental cancer drug, already closely watched by investors, got more attention Wednesday after the company announced new alliances with three other drugmakers to test it in combination with their drugs.
The news temporarily drove Merck shares to a six-year high of $55.20. They fell back as broader markets slumped and by early afternoon were trading at $53.65, up 14 cents.
The drug, known as MK-3475, is part of a promising new class of cancer "immunotherapy" designed to make the immune system regain its ability to identify and then target cancer cells.
In some cancer types, the tumor cells often have a protein on their surface called PD-L1 that essentially acts as an invisibility cloak. Merck's MK-3475 and similar drugs can block that protein, or a corresponding one called PD-1 found on T cells, a crucial immune system component, thus making tumor cells visible.
Early studies of MK-3475, and a drug called nivolumab that Bristol-Myers Squibb Co. is testing, found they shrunk tumors in about one-third of melanoma patients — better than other treatments for the deadliest type of skin cancer. Those drugs also appeared to have less serious side effects than other cancer drugs and in many study participants, tumors kept shrinking for a while after treatment ended.
"This area of medicine, referred to as anti-PD-1 immunotherapy, is a particularly exciting one that could significantly drive future growth," wrote Edward Jones analyst Judson Clark.
Some analysts have speculated the class could become a new gold standard for cancer treatment.
Merck already is running 13 patient tests, expected to enroll more than 4,000 patients, that evaluate the drug against more than 30 cancer types. Those include bladder, colorectal, stomach, head and neck, melanoma, kidney, blood and prostate cancers, plus two types of lung cancer and a subset of breast cancers.
On Wednesday, the Whitehouse Station, N.J.-based company said it's signed deals to test MK-3475 together with cancer drugs from new partners Pfizer Inc., Amgen Inc. and Incyte Corp. That's a smart move, as Merck has few cancer drugs in development.
Merck said its planned studies include giving MK-3475 along with each of two Pfizer drugs to patients with multiple cancer types. One drug is called PF-2566; the other, axitinib, is sold as the brand Inlyta for treating kidney disease.
Merck also will test MK-3475 with Incyte's INCB24360 against multiple advanced cancers, particularly non-small cell lung cancer. And MK-3475 will be tested with an Amgen experimental immunotherapy called talimogene laherparepvec.
Financial terms of the deals were not disclosed. But on a conference call with analysts to discuss Merck's fourth-quarter results, CEO Kenneth Frazier called the deals "very attractive to both parties."
Cancer drugs generally are very lucrative because they command high prices and usually are covered by insurance plans.
Merck said it expects by June to apply for U.S. approval to sell the drug for advanced melanoma.
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