Dr. Monk on the Emergence of NaPi2b as a Target in Ovarian Cancer

Bradley J. Monk, MD, FACS, FACOG, professor, Division of Gynecologic Oncology, Arizona Oncology (US Oncology Network), University of Arizona College of Medicine, Creighton University School of Medicine at St. Joseph’s Hospital, medical director, Gynecologic Program, US Oncology Research Network, co-director, GOG Partners, discusses the emergence and utility of NaPi2b as a target in ovarian cancer.

NaPi2b, a sodium-dependent phosphate transporter, Monk says. NaPi2b is targeted by the investigational antibody-drug conjugate upifitamab rilsodotin (UpRi), which is a humanized monoclonal antibody with a specific linker and a payload of auristatin. The agent also has a high drug-to-antibody ratio, Monk explains. Moreover, the auristatin DolaLock is a controlled by a bystander effect that allows the payload to be selectively released within the tumor, Monk adds.

Overall, research has been done to optimize dosing with UpRi so that patients can continue treatment for an extensive amount of time, Monk continues. The FDA granted UpRi fast track designation in August 2020 for the treatment of patients with platinum-resistant high-grade serous ovarian cancer who have received up to 3 prior lines of systemic therapy or 4 prior lines of systemic therapy regardless of platinum status. Moreover, the first-in-human phase 1/2 UPLIFT study (NCT03319628) is currently enrolling patients with platinum-resistant ovarian cancer or metastatic non–small cell lung cancer to evaluate the safety and efficacy of UpRi in tumors likely to express NaPi2b, Monk concludes.