AthenexThe biotech Athenex (Nasdaq:ATNX) plans to close a facility in Clarence, New York, by March 17, according to a notice from the New York State Department of Labor. It will cut 92 jobs in the process.

The company also noted it would close its 503B sterile compounding business to focus on cell therapy. In the third quarter of 2022, the unit was responsible for roughly 19% of its product sales.

ATNX shares were up 17.90% to $0.17.

On February 5, 2021, its shares traded at $14.00.

Complete response letter from FDA

One factor driving its share price lower was a complete response letter (CRL) from the FDA in March 2022 for its New Drug Application (NDA) for oral paclitaxel with encequidar to treat metastatic breast cancer.

The company’s oral paclitaxel formulation also recently failed to win regulatory approval from the UK’s Medicines and Healthcare Products Regulatory Agency (MHRA) for metastatic breast cancer as a result of Chemistry, Manufacturing and Control (CMC) issues.

Athenex CEO Dr. Johnson Lau noted that the company had addressed major concerns about oral paclitaxel’s clinical efficacy and safety. The company believes the CMC issues that prevented MHRA approval are addressable.

Paclitaxel, whose brand name is Abraxane, won FDA approval in 1992 to treat ovarian cancer. An indication followed in 1994 for advanced breast cancer.

The iSPY 2 study

The oral form of the drug was included among the treatment options of the Phase 2 iSPY 2 TRIAL (Investigation of Serial studies to Predict Your Therapeutic Response with Imaging and Molecular AnaLysis 2, NCT01042379).

The iSPY 2 study provided “an important data set that further characterizes the safety profile of oral paclitaxel, and we plan to amend our metastatic breast cancer NDA with the iSPY 2 safety data this quarter,” Lau said in a news release.

FDA’s complete response letter noted that the oral paclitaxel arm in a clinical trial appeared to be associated with an increased risk of neutropenia-related sequelae compared to those receiving IV paclitaxel.