Phase II clinical trial of S‐1 plus nanoparticle albumin‐bound paclitaxel in untreated patients with metastatic gastric cancer

The present study is the first phase II clinical trial aimed to evaluate the efficacy and safety of S‐1 plus nanoparticle albumin‐bound paclitaxel (Nab‐PTX) as first‐line chemotherapy for advanced gastric cancer (AGC). Previously untreated patients with metastatic gastric adenocarcinoma received S‐1 in oral doses of 40 mg (BSA <1.25 m(2)), 50 mg (1.25 ≤ BSA < 1.50 m(2)) and 60 mg (BSA ≥1.50 m(2)) b.i.d. on days 1‐14 in combination with Nab‐PTX (120 mg/m(2), on days 1 and 8) for each 21‐day cycle. Primary endpoint was progression‐free survival (PFS), and secondary endpoints were overall response rate (ORR), overall survival (OS), disease control rate (DCR), and toxicity. A total of 73 gastric cancer patients with metastatic and measurable lesions were enrolled in the first‐line setting. Median PFS and OS were 9.63 months and 14.60 months, respectively. Four (5.5%) patients had complete responses, 39 (53.4%) had partial responses (PRs), 21 (28.8%) had stable disease, four (5.5%) progressed and five (6.8%) were not evaluable. ORR and DCR were 58.9% and 87.7%, respectively. Most toxicities were mild, and no treatment‐related deaths occurred. Grade 3 to 4 toxicities occurred in 22 patients (30.1%) as follows: leukopenia (13.7%), neutropenia (12.3%), anemia (5.5%), thrombocytopenia (1.4%), diarrhea (6.8%), vomiting (2.7%), stomatitis (1.4%), peripheral neuropathy (1.4%), and hand‐foot syndrome (1.4%). Seven patients achieved good responses and underwent gastrectomy plus metastasectomy. Thirty (41.1%) patients had S‐1 maintenance with a median of four cycles. S‐1 plus Nab‐PTX is an efficient and safe regimen as first‐line treatment for patients with AGC.