Fixed dose versus body surface area
Dr. Kirshner also said his practice uses a dose of 1 g/m2 of body surface area on a 7/7 schedule rather than a fixed dose as was done in Dr. Khan’s study. “If you use the higher dose, you might have seen a higher response rate because many of our patients, as you know, have a body surface [BSA] area much greater than 1.5 g/m2.”
Dr. Khan responded that there is little data available on BSA dosing. “We selected 1,500 mg because a lot of people are practicing that, and for convenience, and that most patients who started at a higher dose eventually wound up on a dose of 1,500 mg twice daily.”
Dr. Kirshner also pointed out that the study was conducted in a population with metastatic disease. “I think we need to emphasize that we do not use the 7/7 regimen in a potentially curative setting, such as the CREATE-X regimen for triple-negative [breast cancer].”
Dr. Khan agreed. “I would use the same dose as the CREATE-X trial in the adjuvant setting,” he responded.
Dr. Danso has received honoraria from Amgen and has consulted or advised Immunomedics, Novartis, Pfizer, and Seagen. Dr. Khan and Dr. Kirshner have no relevant financial disclosures.