In the Matterhorn trial, how many cycles of neoadjuvant and adjuvant FLOT (fluorouracil, leucovorin, oxaliplatin, and docetaxel) are given to patients with gastric or gastroesophageal junction cancer?

MATTERHORN Trial FLOT Dosing Schedule

In the MATTERHORN trial, patients received 4 cycles of neoadjuvant FLOT before surgery and 4 cycles of adjuvant FLOT after surgery, for a total of 8 cycles of perioperative chemotherapy. 1

Neoadjuvant Phase

• 4 cycles of FLOT were administered preoperatively in the MATTERHORN trial 1
• Each FLOT cycle was given every 2 weeks, totaling 8 weeks of neoadjuvant treatment before surgery 2, 1
• The regimen consisted of fluorouracil 2,600 mg/m² as a 24-hour infusion, leucovorin 200 mg/m², oxaliplatin 85 mg/m², and docetaxel 50 mg/m², all on day 1 of each 2-week cycle 2, 3

Adjuvant Phase

• 4 cycles of FLOT were administered postoperatively following surgical resection 1
• The adjuvant cycles used the identical dosing schedule as the neoadjuvant phase 1
• This totaled an additional 8 weeks of chemotherapy after surgery 2

Key Trial Design Features

• The MATTERHORN trial compared perioperative durvalumab plus FLOT versus placebo plus FLOT in resectable gastric and gastroesophageal junction adenocarcinoma 1
• Surgery was performed after completion of the 4 neoadjuvant cycles 1
• The 4+4 cycle approach (4 preoperative + 4 postoperative) represents the standard FLOT perioperative regimen established by the FLOT4-AIO trial 4, 2, 3

Clinical Context

• This 4+4 cycle perioperative approach differs from earlier regimens like ECF/ECX which used 3 preoperative and 3 postoperative cycles 4, 3
• The FLOT4-AIO trial demonstrated superior overall survival with 4+4 cycles of FLOT compared to 3+3 cycles of ECF/ECX (median 50 months versus 35 months; HR 0.77; P = 0.012) 4
• Delayed surgery occurred in 10.1% of durvalumab-FLOT patients and delayed initiation of adjuvant treatment in 2.3% 1