[Note: Ben Fidler contributed to this report.] Immunotherapy is one of the most promising new ways to fight cancer, and we’ve followed it closely for some time. One of its main proving grounds is in blood-borne cancers, because some of the immunotherapy methods are, at least for now, easier to target in that direction.
That’s one reason why the upcoming American Society for Hematology conference—and the research abstracts, or previews, that were released this week—have garnered so much attention. An important caveat is that abstracts are often not representative of final data sets. What researchers report next month in San Francisco might be different than what the abstracts reveal.
More cancer immunotherapy news will certainly emerge from the massive volume of abstracts between now and December 6, the first day of ASH. For now, there are several interesting developments to note.
Cancer immunotherapy drugs that attack the PD-1 protein on tumor cell surfaces have made headlines for their effects on solid tumors like melanoma. But the ASH abstracts are providing some guidance how they might work against blood cancers.
The initial results seem encouraging: Some 87 percent of Hodgkin’s lymphoma patients who had failed at least three prior therapies responded to nivolumab (Opdivo) from Bristol-Myers Squibb (NYSE: [[ticker:BMY]]). Pembrolizumab (Keytruda) from Merck (NYSE: [[ticker:MRK]]) also showed early promise. (Pembrolizumab is approved to treat melanoma in the U.S., nivolumab is approved in Japan but not yet in the U.S.)
One hematological cancer that might not respond as well to PD-1 blockers is multiple myeloma. Bristol-Myers Squibb reported that none of the 27 patients with the disease responded to nivolumab. That’s a boon for Summit, NJ-based Celgene (NASDAQ: [[ticker:CELG]]), as PD-1 drugs represented a potential competitive threat to its multiple myeloma franchise.
Another kind of immunotherapy is based on a patient’s own immune cells, removed and genetically engineered to be efficient killers of a specific type of tumor, and re-introduced to the patient. It’s called chimeric antigen receptor T-cell, or CAR-T, therapy.
One of the leaders in the field is Seattle’s Juno Therapeutics, which is pushing forward into human trials with CAR-T therapy and another kind of immunotherapy developed at three institutions: Memorial Sloan-Kettering Cancer Center in New York, Fred Hutchinson Cancer Research Center in Seattle, and Seattle Children’s Hospital.
Juno has already made a splash, not just with its prodigious fundraising, but with results of a Phase 1 CAR-T trial in which 20 of 22 acute lymphoblastic leukemia (ALL) patients with a particularly intractable form of the disease—in other words, a very grim prognosis—showed complete remission of the disease.
At ASH, Memorial Sloan-Kettering researchers will present follow-up data from those patients. That’s important because some of the most promising medical technologies have seemed transformative at first—and CAR-T cell therapy, which Juno and others are pursuing, fits that description—only to run into the frustrating intricacies of biology.
From the abstract, here’s the latest on those 20 patients. As of July, 1, five had relapsed. Three of them were re-treated, and two of them “achieved a second CR”—or complete remission. That leaves three of the 20 with uncertain status, but the overall results remain impressive in a patient population with little hope of remedy. We contacted Juno officials for comment, but they did not respond in time for publication.
Another important follow-up with these patients are the data on a known side effect of CAR-T called “cytokine release syndrome,” sometimes called