(Gastric/GEJ Cancer) ASCO-GI 2018: Phase Ib/II Trial Report on Second-Line Pembrolizumab Plus Margetuximab

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Originally posted: April 6, 2018

At the ASCO Gastrointestinal Cancers Symposium (ASCO-GI 2018), held in San Francisco on January 18–20, 2018, Dr. Daniel V.T. Catenacci of the University of Chicago Pritzker School of Medicine presented results from a Phase Ib/II clinical trial (NCT02689284). The trial evaluated the anti-PD-1 antibody pembrolizumab (Keytruda) combined with the anti-HER2 antibody margetuximab as second-line treatment in patients with advanced HER2-positive gastric or gastroesophageal junction (GEJ) adenocarcinoma previously treated with trastuzumab.

Trial design

Second-line treatment in 21-day cycles
Pembrolizumab 200 mg plus margetuximab 10 mg/kg (9 patients) or 15 mg/kg (48 patients)
Primary endpoint: response rate

Reported results

In the 15 mg/kg cohort, 38 of 48 patients were evaluable
Partial response: 18.4% (7 patients); stable disease: 28.9% (11 patients)
Response rate by region: North American patients (30) 8.3%, Asian patients (18) 35.7%
Safety: one serious adverse event was reported

Points to consider

These are early results from a small single-arm trial presented at a conference, and they are not sufficient evidence for this combination. Margetuximab is not approved in Japan, and this combination is not an approved treatment in Japan.

Source: Catenacci DVT, et al. ASCO-GI 2018, Abstract No. 140 (Phase Ib/II trial, NCT02689284)

Note: This article summarizes overseas clinical research for reference only and is not medical or treatment advice. Study data do not predict outcomes for individual patients. Please refer to the original source and discuss any treatment decisions with your physician.

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