Фармакоэкономические аспекты применения ингибиторов циклинзависимых киназ 4 и 6 в первой линии терапии местнораспространенного или метастатического рака молочной железы Оптимизация лекарственного обеспечения пациентов со злокачественными новообразованиями на уровне субъекта Российской Федерации Оценка технологий здравоохранения в Австралии Том 12 2019 FARMAKOEKONOMIKA Modern

Introduction. The presence of a germinal BRCA mutation occurs in 3–4% of all breast cancer (BC) patients with various biological subtypes, but significantly with a high frequency in patients with a triple negative biological subtype (in 10–20% of cases). For the treatment of patients with HER2-negative metastatic breast cancer associated with gBRCA mutation, the effectiveness of biologically targeted drugs from the group of PARP inhibitors (olaparib and talazoparib) has been proven.Purpose. Comparison of the results of our experience with the use of talazoparib in patients with HER2-gBRCA+ + mBC with the data of the EMBRACA registration study.Materials and methods. As part of the multicenter compassionate use program (CUP) with the support of Pfizer, 24 patients with HER2-negative metastatic gBRCA-associated mutation metastatic breast cancer (HER2-gBRCA+ breast cancer) received biologically targeted therapy with the PARP inhibitor talazoparib at a standard oral dose of 1 mg per day for vital indications . The average age of patients with HER2-gBRCAm+ breast cancer was 50 years (29–90 years).Results. Objective response (OR) was registered in 29% of cases, disease control (OR+stabilization) – in 71% of cases. The median progression-free survival (PFS) was 6.5 months (95% CI [3–10]). Objective response, disease control, and median PFS were evaluated depending on the biological subtype, the number of lines of previous therapy, and the presence of platinum-containing agents in the anamnesis.Objective response and disease control were evaluated depending on the biological subtype: in patients with ER+HER2-mBC versus patients with triple negative subtype, OR was 33% vs 22%, and disease control was 83% vs 61%, respectively. In the presence of < 3 vs ≥ 3 lines of therapy for metastatic disease in the anamnesis, OR was 31% vs 12.5%, disease control – 75% vs 50% of cases, respectively. In the presence or absence of platinum-containing agents in the anamnesis, OR was observed in 22% vs 33% of cases, and disease control – 67% vs 67%, respectively.In patients with the luminal subtype versus patients with the triple negative subtype, the PFS was 9 months vs 5 months, respectively (HR = 0.705; 95% CI [0.231–2.147]; p = 0.5208). Median PFS in the presence of <3 vs ≥3 lines of therapy for metastatic disease in the anamnesis was 9 months vs 4 months, respectively (HR = 4,216; 95% CI [1,334–13,327]; p = 0.0056). In the presence or absence of platinum-containing agents in previous lines of therapy 5 months vs 9.5 months, respectively (HR =1.484; 95% CI [0.48–4.582]; p = 0.4750).During the treatment with talazoparib adverse events of the 3rd-4th grades were observed in 5 patients (20,8%). These include moderate and severe anemia in 3 patients (12.5%), thrombocytopenia in 1 patient (4%), and neutropenia in 1 patient (4%). The majority of patients (79,5%), which received talazoparib, did not require dose adjustment. The need to reduce the dose to 0.75 mg was noted in 3 patients (12.5%), to 0.5 mg – in 2 patients (8%). Hemotransfusion was performed in 3 patients. For effective therapy safety management regular monitoring of blood parameters is necessary.Conclusion. Thus, targeted therapy with talazoparib is an effective treatment option for HER2-gBRCA+ mBC.

Background. Treatment results for the patients with stage II–III triple negative breast cancer (TN BC) have to be improved. Not only the new treatment regimens, but new predictive and prognostic factors should to be developed.Materials and methods. We included 98 patients with stage II–III TN BC in our study. We studied efficacy and safety of PlaTax regimen (cisplatin 75 mg / m2 day 1 + paclitaxel 80 mg / m2 days 1, 8, 15, course every 4 weeks) in this cohort of patients. We assessed pathologic response, survival and factors, which were relevant for predicting response and prognose survival.Results. PlaTax regimen is characterized by high efficacy and tolerable toxicity. Clinical efficacy was 85.8 %, pCR achievement was 60.5 %, tpCR achievement was 58.1 %. The regimen has low haematological toxicity (neutropenia III–IV grades – 4.1 %); the most frequent adverse events were polyneuropathy (18.5 %) and decreased renal function (24.5 %). 3-year progression-free survival was 68.4 %, most of the relapses (92 %) occurred during first 2 years. 3 year overall survival was 77.6 %. The most relevant predictive factor was level of Ki-67 ≥50 % (pCR 38.5 % vs. 68.7 %, p = 0.038). pCR achievement was the most important prognostic factor, resulting in improved 3-year progressionfree survival (44.3 % vs. 89.1 %, p <0.0001), and 3-year overall survival (61.5 % vs. 91.6 %, p = 0.001). Not only the residual disease, but also the size of residual tumor was important from prognostic point of view. Other important prognostic factors were size of the tumor, status of regional lymph nodes, grade. Delay in surgical treatment more than a month lead to decreased 3-year progression-free survival: 87.1 % vs. 62.5 % (p = 0.047).Conclusions. Our data suggest that studied regimen could be an option for patients with stage II–III TN BC. The assessment of the predictive and prognostic factors will help improve the treatment results for patients with stage II–III TN BC.

Breast cancer steadily holds leading market positions in the malignancy morbidity and mortality pattern. The treatment of metastatic breast cancer remains an extremely topical issue, when its aim is not only to prolong the patient’s life, but also to preserve its quality. Due to advances in molecular diagnostics, it has become possible to use several new classes of drugs in recent times. CDK4/6 inhibitors that demonstrate high efficacy in the first-line therapy for luminal metastatic breast cancer is one of these groups. This review presents data from recent registration studies and a description of observations from our own clinical experience.