Scott T. Tagawa, MD, MS, FACP, FASCO, is a professor of medicine and urology at Weill Cornell Medicine and an attending physician at NewYork-Presbyterian – Weill Cornell Medical Center in New York.

Scott T. Tagawa, MD, Weill Cornell Medicine/New York-Presbyterian, discusses updated results from the IMMU-132 trial in metastatic urothelial cancer (mUC).

In the study, patients who were pretreated with platinum-containing chemotherapy received IMMU-132, an anti-Trop-2-SN-38 antibody-drug conjugate.

Of 44 patients, 36 are evaluable for response—which met the primary endpoint. At the time of these results, the response rate is above 30% and durable.

View more from the 2017 Genitourinary Cancers Symposium

Videos

Dr. Tagawa on IMMU-132 Trial Updates in Urothelial Cancer

Scott T. Tagawa, MD, MS, assistant professor of Medicine, medical director, Genitourinary Oncology Research Program, assistant attending physician, New York-Presbyterian Hospital, discusses the antibody-drug conjugate IMMU-132 for the treatment of patients with metastatic platinum-resistant urothelial cancer.

IMMU-132 is an anti—TROP-2 antibody-drug conjugate comprised of SN-38. Regarding safety, the agent is not as toxic compared with other antibody-drug conjugates, Tagawa explains. In a phase I/II study, grade 3 neutropenia was observed in patients who received IMMU-132, but grade 1/2 diarrhea was one of the most common adverse events.

Preliminary findings demonstrate a median progression-free survival of 8.1 months with 50% maturity, and a median overall survival of 10.8 months, with 79% of patients still alive.

Dr. Scott Tagawa Discusses IMMU-132  in Patients With Urothelial Carcinoma

Scott T. Tagawa, MD, assistant professor of medicine, medical director, Genitourinary Oncology Research Program, Weill Cornell Medical College, discusses the molecular characterization of circulating tumor cells (CTCs) in neuroendocrine-positive prostate cancer.

In prostate cancer, there has been a problem with molecular characterization because it was traditionally difficult to biopsy bone. By counting and analyzing CTCs, physicians can characterize the disease, Tagawa says.

CellSearch, the platform that captures and counts CTCs, is generic and does not rely on a specific protein or antigen. Less is known about the neuroendocrine subset of prostate cancers because it only exists in about 25% of prostate cancer patients, Tagawa says. A study captured CTCs in neuroendocrine patients and characterized them. Tagawa says this study, although small, proves that CTCs have utility in this subset of patients.

Dr. Tagawa on CTCs in Neuroendocrine Prostate Cancer

Scott T. Tagawa, MD, assistant professor of medicine, medical director, Genitourinary Oncology Research Program, Weill Cornell Medical College, discusses the results of a study that evaluated the safety of abiraterone acetate combined with docetaxel in patients with metastatic castration-resistant prostate cancer that were presented at the 2014 Genitourinary Cancer Symposium in San Francisco.

Tagawa says the data presented at the symposium is a preliminary presentation of the full data set for cohorts 1 and 2 with a mention of the first part of cohort 3. In cohort 1, patients received slightly lower doses of both abiraterone and docetaxel while in cohort 2, patients received full doses of docetaxel with a lower dose of abiraterone. Cohort 3 treated patients to full doses of both drugs, Tagawa says.

The results of the data from cohorts 1 and 2 showed that there were no unexpected dose-limiting toxicities. A full pharmacokinetic evaluation was done for each drug alone as well as in combination, Tagawa says. This showed that there were no significant differences from expectations in toxicity for the combination.

Tagawa says the combination is interesting because there is a theory that the mechanisms of actions for the two drugs are similar in their approach to targeting the AR pathway. It was recently discovered that early chemotherapy has a longer-term benefit in overall survival, which could bring docetaxel back into an early setting, Tagawa believes.

Preliminary efficacy data showed that each patient had at least a 50% decrease in PSA. Additionally, 80% of the patients had at least a 90% decrease in PSA at some point during treatment, Tagawa notes.

View more from the 2014 GU Cancers Symposium

Scott T. Tagawa, MD

Articles

Dr. Tagawa on IMMU-132 Trial Updates in Urothelial Cancer

Dr. Scott Tagawa Discusses IMMU-132 in Patients With Urothelial Carcinoma

Dr. Tagawa on CTCs in Neuroendocrine Prostate Cancer

Dr. Tagawa on Abiraterone Plus Docetaxel in mCRPC