NALA: Neratinib–capecitabine role in HER2-positive MBC confirmed in Asians

The neratinib/capecitabine combination still confers survival advantage over lapatinib plus capecitabine in the subgroup of Asian patients with heavily treated HER2-positive metastatic breast cancer (MBC), according to an exploratory analysis of the phase III NALA trial.

Findings from the pan-Asian subgroup of patients were consistent with those observed in the overall NALA population, according to Dr Ming Shen Dai of the Tri-Service General Hospital - Neihu Branch in Taipei, Taiwan, who presented their data during the European Society for Medical Oncology (ESMO) Asia Virtual Congress 2020.

Specifically, neratinib/capecitabine significantly prolonged survival and improved response compared with the lapatinib combination in the previously treated HER2-positive MBC population, Dai added.

The current pan-Asian subgroup analysis included 202 Asian patients within the intention-to-treat population. The majority of them (63.9 percent) were Chinese from Taiwan and Hong Kong.

In total, 104 patients received the neratinib combination and 98 were treated with the lapatinib combination. All of them had received at least two prior HER2-targeted regimens in the metastatic setting. Neratinib was administered at 240 mg once daily with capecitabine at 750 mg/m² twice a day, whereas lapatinib was given at 1,250 mg once daily in combination with twice-daily capecitabine at 1,000 mg/m² on days 1–14 in 21-day cycles.

The neratinib versus lapatinib combination was associated with a longer progression-free survival (PFS; median, 7.0 vs 5.4 months), with a 42-percent reduction in the risk of progression (hazard ratio [HR], 0.58, 95 percent confidence interval [CI], 0.41–0.81; p<0.001). Six-, 12-, and 18-month PFS rates with the respective treatments were 53.7 percent versus 33.8 percent, 33.5 percent versus 10.0 percent, and 19.9 percent versus 4.0 percent. [ESMO Asia 2020, abstract 46O]

Dai noted a positive trend in overall survival (median, 23.8 vs 18.7 months; HR, 0.79, 95 percent CI, 0.56–1.12; p=0.185).

Results for the secondary outcomes were also more favourable with neratinib/capecitabine. Fewer patients required intervention for central nervous system metastases (27.9 percent vs 33.8 percent; p=0.039) than in the lapatinib/capecitabine arm. Objective response rate (40.7 percent vs 32.1 percent), duration of response (median, 11.1 vs 4.2 months), and clinical benefit rate (51.9 percent vs 40.5 percent) were all better with the neratinib combination.

Diarrhoea was a concern in both treatment arms (78.8 percent with neratinib vs 51.0 percent with lapatinib), according to Dai. However, these events were only mild to moderate in severity (grade ≤3) and led to few instances of treatment discontinuation (1.0 percent vs 0.0 percent).

“Neratinib, an irreversible pan-HER tyrosine kinase inhibitor, [in combination with capecitabine], has been approved for the indication of HER2-positive MBC and early HER2-positive breast cancer,” Dai said.

Data from the NALA trial served as the basis for the US Food and Drug Administration approval of the neratinib combination for advanced or metastatic HER2-positive breast cancer in February this year. [bit.ly/36YdBQW]