A phase II study of carboplatin and cyclophosphamide in advanced ovarian carcinoma

Anaemia and pathologic complete response rate according to carboplatin dose in HER2+ breast cancer treated with neoadjuvant TCHP

Grade 3/4 anaemia, which is mainly induced by carboplatin, frequently occurs in patients treated with neoadjuvant docetaxel/carboplatin/trastuzumab/pertuzumab (TCHP). However, dose reduction of carboplatin may raise concerns about the oncological outcome. This study investigated the pathologic complete response (pCR) rate, occurrence of grade 3/4 anaemia, and transfusion rate according to carboplatin dose in patients treated with neoadjuvant TCHP. We retrospectively analysed 294 patients treated with neoadjuvant TCHP between April 2015 and December 2020. Case matching was performed using propensity score matching. Among patients treated with neoadjuvant TCHP, carboplatin area under the plasma concentration-time curve 6 (AUC6) was used in 234 patients (79.6%) and upfront carboplatin AUC5 was used in 60 patients (20.4%). No significant difference in pCR rate was found between the two groups (AUC6: 70.9%, AUC5: 80.0%). In both oestrogen receptor-positive (ER+) and ER- patients, no significant differences were observed between the AUC6 and AUC5 groups (ER+: 54.3% vs. 50.0%, ER-: 81.7% vs. 86.0%). The case-matched cohort showed consistent findings. The AUC5 group had lower frequencies of grade 3/4 anaemia (18.3% vs. 34.2%) and transfusion events (10.0% vs. 21.8%) than the AUC6 group. Compared with AUC5, carboplatin at AUC6 would associate with a 2.7-fold increased risk of grade 3 or 4 chemotherapy-induced anaemia. Carboplatin AUC5 has comparable cytotoxic effects to carboplatin AUC6 in patients with HER2+ breast cancer treated with six cycles of neoadjuvant TCHP, with fewer complications associated with clinically meaningful anaemia. AUC5 may be the optimal carboplatin dose to reduce TCHP-induced anaemia in patients with HER2+ breast cancer treated with TCHP.

Association of cyclophosphamide pharmacokinetics to polymorphic cytochrome P450 2C19

Cyclophosphamide (CP), a widely used cytostatic, is metabolized by polymorphic drug metabolizing enzymes particularly cytochrome P450 (CYP) enzymes. Its side effects and clinical efficacy exhibit a broad interindividual variability, which might be due to differences in pharmacokinetics. CP-kinetics were determined in 60 patients using a global and a population pharmacokinetic model considering functionally relevant polymorphisms of CYP2B6, CYP2C9, CYP2C19, CYP3A5, and GSTA1. Moreover, metabolic ratios were calculated for selected CP metabolites, analyzed by (31)P-NMR-spectroscopy. Analysis of variance revealed that the CYP2C19*2 genotype influenced significantly pharmacokinetics of CP at doses </=1000 mg/m(2), whereas there was no evidence of an association of other genotypes to CP elimination or clearance. Mean (+/-SD) CP elimination constants k(e) (h(-1)) were 0.109+/-0.025 in 44 CYP2C19*1/*1 subjects, 0.088+/-0.018 in 13 CYP2C19*1/*2, and 0.076+/-0.014 in three inactive CYP2C19*2/*2 carriers (P=0.009). At CP doses higher than 1000 mg/m(2), a significantly increase of elimination was observed (P=0.001), possibly due to CYP induction. Further studies should link these findings with the clinical outcome.

Second-line carboplatin and gemcitabine in platinum sensitive ovarian cancer--a dose-finding study by the Arbeitsgemeinschaft Gynäkologische Onkologie (AGO) Ovarian Cancer Study Group

BACKGROUND

Despite the progress that has been achieved in the last years, recurrence rates in ovarian cancer patients are still considerably high and the majority of patients ultimately become candidates for second-line treatment. Carboplatin reinduction is a broadly adopted regimen in patients with recurrences occurring six months or later after first-line treatment. Gemcitabine is among the candidates as combination partner in second-line regimens.

PATIENTS AND METHODS

We performed a study with escalating doses of gemcitabine combined with carboplatin in 26 platinum-pretreated patients with recurrent ovarian cancer and a treatment-free interval of 6+ months. Dose-limiting toxicity (DLT) and a maximum tolerable dose (MTD) recommendable for further trials was evaluated.

RESULTS

The DLT was myelosuppression, mainly thrombocytopenia. No dose limiting non-hematological toxicities were observed. The MTD of gemcitabine was 1,000 mg/m2 given on days 1 + 8 of a three-week schedule combined with carboplatin AUC 4 given on day 1. The majority of evaluable patients showed an objective response (62.5%), and median progression-free and overall survival were 10 and 18+ months, respectively.

CONCLUSION

Gemcitabine-carboplatin given according to the MTD is well tolerated and active against recurrent platinum-sensitive disease. A randomized trial comparing carboplatin with or without gemcitabine in platinum-sensitive ovarian cancer has already been initiated.