Spectrum Pharmaceuticals, Inc. (NASDAQ: SPPI) stock plummet 38.79% on December 20th, 2018 (Source: Google finance) after the company the Food and Drug Administration refused to designate the company’s lung cancer candidate a Breakthrough Therapy. According to the FDA, breakthrough therapy designation is for a drug that treats a serious or life-threatening condition and preliminary clinical evidence indicates that the drug may demonstrate substantial improvement on a clinically significant endpoint/s over available therapies. Breakthrough therapy designation can lead to fast-track approval of a drug by the FDA.
Spectrum Pharmaceuticals had already told investors that it submitted a Breakthrough Therapy designation request for poziotinib, so the company couldn’t keep the FDA’s unusual decision to decline that request a secret. The company’s been exciting investors with the hope of accelerated approval for poziotinib as a treatment for relapsed non-small cell lung cancer (NSCLC) patients with a specific mutation, but if it can’t earn a simple breakthrough designation, that probably won’t happen. The company’s overall development plan and timeline for a New Drug Application (NDA) filing based on the first cohort of the ZENITH20 trial remains unchanged. ZENITH20 is a Spectrum-sponsored, open-label, single-arm, multi-center, global Phase 2 study evaluating more than 300 NSCLC patients with EGFR or HER2 exon 20 insertion mutations. The study consists of four cohorts, each of which is independently powered for a pre-specified statistical hypothesis.
Spectrum’s BTD application included data from 30 patients from the MD Anderson Phase 2 study who had failed platinum-based chemotherapy. The data demonstrated a confirmed objective response rate of 40% and median duration of response of 6.6 months. The safety profile in this subset was consistent with historical data published on poziotinib and other tyrosine kinase inhibitors. The historical objective response rates for mutation specific NSCLC patients range between 0% and 8% with tyrosine kinase inhibitors and for non-mutation specific NSCLC patients range between 0.8% and 22.9% with other treatments.
Meanwhile, SPPI announced results from a prospective Phase 2 single-arm, open-label, multicenter clinical trial studying the management of oral mucositis with the use of oral leucovorin (d,l-folinic acid) as adjunct to FOLOTYN® (pralatrexate) in patients with hematological malignancies, including PTCL and CTCL. These new data were highlighted in a poster presentation at the 60th Annual Meeting of the American Society of Hematology (ASH).
In practice, FOLOTYN use has caused Grade 2 or higher oral mucositis in more than half of patients, potentially impacting treatment of relapsed or refractory Peripheral T-cell Lymphoma (PTCL)