Athenex works to get cancer drug to market
Athenex officials are working to ensure the company’s long-term viability — a process that includes FDA approval of oral paclitaxel.
Oral paclitaxel is a breast cancer treatment which has shown promising effectiveness and clinical revelance when used in combination with encequidar. When the federal Food and Drug Administration wrote in a complete response letter in February that concerns regarding safety of the drug because it could lead to low white blood cell counts in the blood as well as concerns about the way Athenex officials structured the oral paclitaxel clinical trial. The FDA letter sent Athenex’s stock prices plummeting and company officials searching for a way to get oral paclitaxel to market safely — both to help those with breast cancer and bring Athenex to profitability.
Athenex officials say their recent discussions with the FDA have been positive. Dr. Rudolf Kwan, Athenex chief medical officer, said FDA officials encouraged Athenex to continue working on oral paclitaxel as a treatment for metastatic breast cancer, though the FDA still wants Athenex to address what FDA officials termed deficiencies in Athenex’s previous trial.
Clinical trials can cost millions, according to a 2018 Johns Hopkins Bloomberg School of Public Health Study — which raised concerns among investor analysts. The FDA’s March complete response letter prompted a 54.6% drop in Athenex’s stock price, likely due in part to the increased cost of an additional trial and the delay in taking oral paclitaxel to market as a breast cancer treatment.
“Regarding oral paclitaxel in metastatic breast cancer, we are certainly pleased that the FDA is supportive of our continued development,” said Johnson Lau, Athenex CEO. “At the same time, we want to be realistic and recognize that conducting another large multiyear study in breast cancer may not be the best use of capital. We’ll continue to work on designing an optimal trial that addresses the deficiencies in the CRL and explore additional pathways. We firmly believe that oral paclitaxel has some compelling clinical profile and can potentially address significant medical needs in multiple indications.”
Athenex officials said several times during last week’s conference call that the company plans to submit a proposal defining the study and to ask for FDA input on the new study design this fall or winter. Investor analysts asked if that meant interim data from the new study would be ready for the fall/winter of 2022. Lau said there is a wide range of potential studies Athenex could undertake to meet the FDA’s request, including if higher U.S. standards of care could mitigate the issues the FDA found with Athenex’s last Phase III trial which was largely focused on Latin America.
“The best interpretation we have from the CRL letter and from the Type A meeting, is that the focus of the FDA is in safety data from a U.S. population from a study that is well conducted,” Kwan said. “So I think that is where we are generally — afford a generally optimal design to address that.”
OTHER USES FOR ORAL PACLITAXEL
While they are still working to get oral paclitaxel to market as a breast cancer treatment, Athenex officials said they are also working on other avenues to maximize the company’s investment in the drug.
Lau said Athenex is working on an additional path for oral paclitaxel through an Orphan Drug Designation. The FDA Office of Orphan Products Development evaluates and develops products — drugs, biologics, devices or medical foods — that demonstrate promise for the diagnosis and/or treatment of rare diseases or conditions.
Athenex officials said oral paclitaxel has received an Orphan Drug Designation because of its potential use treating angiosarcoma, a cancer for which there is no approved treatment. The company is also finishing a Phas1 study of oral paclitaxel’s use in combination with pembrolizumab, better known to the public as Keytruda. An abstract “Phase 1 Study with Expansion Cohorts to Assess the Safety, Tolerability, and Activity of oral paclitaxel + encequidar in Combination with Pembrolizumab in Subjects with Advanced Solid Malignancies” has been accepted for e-Poster presentation at the European Society for Medical Oncology (ESMO) Congress 2021.
“As to our Phase I study of oral paclitaxel in combination with pembrolizumab study in solid tumors, the dose-finding results from this study will be presented at the ESMO Virtual Conference taking place in September,” Rudolf Kwan said. “Our abstract has been accepted for e-poster presentation. We are currently proceeding into the expansion phase of this study for the cohort of lung cancer patients with plans to expand into a second cohort of gastric cancer patients. Lastly, on the I-SPY2 trial, in which oral paclitaxel is being studied in combination with GlaxoSmithKline, dostarlimab and carboplatin for neoadjuvant treatment in breast cancer, this trial is ongoing and progressing well.”