Seattle Genetics and its partner, Millennium: The Takeda Oncology Company, are following one of the well-traveled roads in cancer drug development. It’s about first gaining experience in the market by treating a small group of the very sickest patients, then working backwards until your drug eventually becomes part of the standard of care for more people who are newly diagnosed.
If the drug proves super-effective and safe over time, it could end up as part of “maintenance” therapy to keep the cancer from coming back.
It’s all part of the long-term strategy at Seattle Genetics (NASDAQ: [[ticker:SGEN]]), which will be on display next week at the American Society of Hematology‘s big annual meeting in San Diego. The company will have a handful of presentations this year about its antibody drug, brentuximab vedotin (Adcetris), for lymphomas. The treatment was initially cleared in the U.S. for patients with relapsed and treatment-resistant forms of Hodgkin’s lymphoma and anaplastic large cell lymphoma. But now Seattle Genetics and Millennium are preparing to release some results at ASH from a small trial of patients with a much healthier prognosis—those getting their first line of therapy for Hodgkin’s disease.
Genentech followed a similar strategy with its hit rituximab (Rituxan) for non-Hodgkin’s lymphoma, says Seattle Genetics CEO Clay Siegall. It started with relapsed, treatment-resistant patients, moved into the standard of care for newly diagnosed patients, and became part of maintenance therapy. If Seattle Genetics can duplicate the feat, it will significantly expand the potential market for its drug, and provide the first advance for this group of patients since the existing chemo regimen was established in 1977.
“After 34 years of there being no advances in front-line therapy, our goal is to increase the efficacy and decrease the toxicity,” Siegall says.
About 9,000 patients in the U.S., and a similar number in Europe, are diagnosed with Hodgkin’s each year, and are generally prescribed a cocktail of four chemotherapy drugs that essentially effective for 80-90 percent of patients, Siegall says. The bet for Seattle Genetics and Millennium is that the new antibody drug can raise the bar even higher on effectiveness, while reducing some of the nastier side effects of chemotherapy, including lung scarring.
The standard of care is a combination of chemotherapy drugs Adriamycin, bleomycin, vinblastine, and dacarbazine, known as ABVD. Based on feedback from top researchers, Seattle Genetics is testing the idea that the “B” in that regimen (bleomycin) might be the nastiest ingredient in the mix. The idea is to swap out bleomycin, and swap in the Seattle Genetics drug, Siegall says.
Researchers are keen to test this idea based on how the Seattle Genetics drug has performed in the sickest patients. The Seattle Genetics drug provided significant tumor shrinkage in 75 percent of patients with relapsed forms of Hodgkin’s disease in a clinical trial, and in about 86 percent of patients with anaplastic large-cell lymphoma. Researchers are still following patients to see how long those responses really do last, and to what extent they may help people live longer. The most common side effects found