The role and efficacy of Pertuzumab

Pertuzumab (Pertuzumab) is a humanized monoclonal antibody targeting the HER2 receptor. It represents a promising new anti-HER2 drug with a new mechanism of action that targets HER2 dimerization. Nonclinical and clinical data to date suggest that pertuzumab provides broader HER2 blockade by inhibiting HER2 heterodimerization. In preclinical trials, pertuzumab showed superior anti-tumor effects when used in combination with other anti-HER2 treatments, such as trastuzumab, compared with when used alone. Intravenous pertuzumab was acceptable tolerable when added to trastuzumab and chemotherapy.

In one study, patients with HER2-positive advanced breast cancer who had disease progression on prior trastuzumab therapy received trastuzumab weekly (4 mg/kg loading dose, then 2 mg/kg weekly) or every 3 weeks (8 mg/kg loading dose, then 6 mg/kg every 3 weeks) and pertuzumab every 3 weeks (840 mg loading dose, then 420 mg every 3 weeks). The phase II trial evaluated the efficacy and safety of the combination with an objective response rate of 24.2% and a clinical benefit rate of 50%. Five patients (7.6%) experienced a complete response, 11 patients (16.7%) experienced a partial response, and 17 patients (25.8%) experienced stable disease for 6 months or longer. Median progression-free survival (PFS) was 5.5 months. Overall, the combination of pertuzumab and trastuzumab was well tolerated, with mild to moderate adverse effects.

The most common adverse reactions of grade 3 or above were neutropenia, febrile neutropenia and leukopenia. The study concluded that patients treated with pertuzumab and trastuzumab plus docetaxel had significantly improved pathologic complete response rates compared with patients treated with trastuzumab plus docetaxel alone, suggesting that a chemotherapy backbone is necessary to improve pCR rates. The addition of pertuzumab to the trastuzumab plus docetaxel regimen did not significantly affect overall safety, and the tolerability of pertuzumab plus docetaxel was roughly equivalent to that of the triple regimen.

Pertuzumab is a strictly controlled drug. The original drug has been marketed in China and has entered the ranks of medical insurance, but it is only reimbursed for patients who meet the indications. The price of each box may be more than more than 5,000 yuan, and the price of the Hong Kong version may be more than 20,000 yuan (the price may fluctuate due to exchange rates). The price of each box of the European version of Pertuzumab's original drug marketed overseas may be more than 10,000 yuan, and the price of each box of the Turkish version may be more than 6,000 yuan (the price may fluctuate due to exchange rates). The ingredients of the domestic and foreign original drugs are basically the same, and there are currently no generic versions of Pertuzumab on the market.