October 14, 2016
By Mark Terry, BioSpace.com Breaking News Staff
Bothell, Washington-based Seattle Genetics has been busy expanding and growing, building-out new headquarters, and hiring about 100 new staffers each year. Which makes one wonder why Julian and Felix Baker, who run Baker Brothers Advisors, a health care hedge fund, might be selling their 44 million shares in the company.
Baker Brothers filed a supplemental prospectus with the U.S. Securities and Exchange Commission (SEC) that registered their 44 million shares, which is about 31 percent of the company. Although there’s no obvious indication they plan to sell, the prospectus allows them to. Felix Baker is also on the company’s board of directors.
Adam Feuerstein, writing for TheStreet, doesn’t have any conclusions, other than to say, “Registering 44 million shares in any biotech company is an eye opener and worth watching.”
Otherwise, things have been going well for the company. In July, Seattle Genetics, along with Takeda Pharmaceutical Company in Osaka, Japan, announced final data for its Adcetris (brentuximab vedotin) monotherapy Phase II clinical trial. They reported positive results in patients with relapsed or refractory classical Hodgkin lymphoma. The U.S. Food and Drug Administration (FDA) approved Adcetris for the treatment of classical Hodgkin lymphoma after failure of autologous hematopoietic stem cell transplantation, for the treatment of classical Hodgkin lymphoma patients at high risk of relapse or progression, and accelerated approval in patients with systemic anaplastic large cell lymphoma (SALCL) after failure of at least one prior multi-agent chemotherapy regimen.
In 2012, the European Commission granted conditional marketing authorization for the drug to treat adult patients with relapsed or refractory CD30-positive Hodgkin lymphoma following autologous stem cell transplant (ASCT) and in patients with relapsed or refractory sALCL.
The drug is also being evaluated in more than 70 ongoing clinical trials. Adcetris brought in $226 million last year.
In addition, on August 1, the two companies announced positive news in the Phase III ALCANZA trial of Adcetris in cutaneous T-cell lymphoma (CTCL). And on September 19, Seattle Genetics enrolled its first patient in a Phase I trial of SGN-CD123A in patients with relapsed or refractory acute myeloid leukemia (AML). The drug is an antibody-drug conjugate (ADC) that targets CD123 using the company’s proprietary technology, an engineered cysteine antibody (EC-mAb) that is stably linked to a potent DNA binding agent, pyrrolobenzodiazepine (PBD) dimer.
On October 7, the company, along with Agensys, an affiliate of Astellas , presented clinical data for enfortumab vedotin (ASG-22ME) and ASG-15ME at the European Society for Medical Oncology (ESMO) Congress held in Copenhagen, Denmark. The two drugs are both ADCs that target cell surface proteins, Nectin-4 and SLITRK6, respectively. So far, both compounds show overall response rates in patients with previously treated metastatic urothelial cancer, including those that have prior checkpoint inhibitors. Phase II safety and recommended doses were also presented.
“We are pleased to advance the enfortumab vedotin development program for patients with metastatic urothelial cancer,” said Jonathan Drachman, Seattle Genetics’ chief medical officer and executive vice president, Research and Development, in a statement. “These patients are in dire need of new treatment options as their prognosis is grim, with a five-year survival rate of about 15 percent. The antitumor activity and safety profile of enfortumab vedotin in heavily pretreated metastatic patients is encouraging, particularly in those patients who have failed both platinum-based chemotherapy and checkpoint inhibitors. We look forward to discussions with regulatory agencies.”
