359 Paclitaxel by 3-H on day 1 & 8 every three-weeks in women with anthracycline-resistant metastatic breast cancer

Frequent administration by 3-h infusion should result in prolonged and intense tumor exposure to active concentrations of P. In May 1994 we started a trial to assess feasibility, maximum tolerated dose (MTD) and antitumor activity of P on day 1 and 8 q 3 wk schedule. After standard premedication P was infused in 3-h starting at 100 mg/m 2 . Dose escalation by 25 mg/m 2 steps in subsequent cohorts of patients (pts) was planned. Twenty pts with metastatic breast cancer were accrued so far (10 at 100, and 10 at 125 mg/m 2 ). Median age was 50 (22–59) and ECOG PS 0 (0–2). Thirteen pts had relapsed and 7 progressed within median 7 months (1–20) of prior anthracyclines. Fourteen pts and 70 cycles are presently evaluable for rexicily and 13 pts for activity. Main toxicities according to WHO scale were: dose patients neutropenia neuropathy myalgias (mg/m 2 ) (n.) III IV I II I II 100 10 3 1 6 1 2 2 125 4 2 - 2 1 2 - All patients had grade 3 alopecia. Nansea was rare. Dominant sites of measurable disease in 13 pts were: lung (n = 7), liver (n = 2), pleura (n = 1), and soft tissue (n = 4). Three CR and 8 PR (84%, C.I.: 55–98%) were observed. Sites of response were lung (6/7), liver (2/2), soft tissue (3/3), and bone (3/4). Median duration of response is 5 months (2+–10+). Four pts had CNS progression while still responding on extra-CNS sites. These preliminary data indicate that the new schedule of P is feasible and very active. The accrual continues to define the MTD and assess the actual duration of responses.