OBJECTIVE: In advanced breast cancer, endocrine therapy is preferred in the absence of visceral crisis. Cyclin-dependent kinase inhibitors (CDKi) are the gold standards. The selection of subsequent treatments after CDKi treatment is still controversial, and the efficacy of everolimus (EVE) combinations is unknown. In this study, we aimed to investigate the efficacy of EVE after CDKi administration in real-life experiences.
METHODS: The study received data from 208 patients from 26 cancer centers. Demographic and histologic features, diagnosis, progression, last visit dates, and toxicities were recorded. This study was a retrospective case series.
RESULTS: One hundred and seven patients received palbociclib, while 101 patients received ribociclib as a CDKi. The overall response and disease control rates of EVE combinations were 60% and 88%, respectively. In univariate analysis, the absence of liver metastasis, age > 40 years, better type of response, and immediate treatment after CDKi were related to increased progression-free survival. Liver metastasis and response type were significantly associated with overall survival. In the multivariate analysis, response remained significant in terms of progression-free survival, while response type, liver metastatic disease, and hematologic toxicity were prognostic in terms of overall survival.
CONCLUSIONS: This study provides evidence of the benefits of EVE combinations after CDKi treatment. EVE combinations may be more appropriate for patients with non-liver metastasis, and the first treatment response shows the benefit of treatment. In addition, immediate treatment after CDKi treatment is more beneficial than later lines of treatment.

BACKGROUND: This phase I trial evaluated the safety and tolerability of milciclib, an inhibitor of multiple cyclin-dependent kinases and tropomycin receptor kinase A, in combination with gemcitabine in patients with refractory solid tumors.
METHODS: Sixteen patients were enrolled and treated with milciclib at three dose levels (45 mg/m2/day, n = 3; 60 mg/m2/day, n = 3; and 80 mg/m2/day, n = 10) with a fixed dose of gemcitabine (1000 mg/m2/day). Milciclib was administered orally once daily for 7 days on/7 days off in a 4-week cycle, and gemcitabine was administered intravenously on days 1, 8 and 15 in a 4-week cycle.
RESULTS: All 16 enrolled patients were evaluable for safety and toxicity. Dose-limiting toxicities, which occurred in only one out of nine patients treated at the maximum dose tested (milciclib 80 mg/m2/day and gemcitabine 1000 mg/m2/day), consisted of Grade 4 thrombocytopenia, Grade 3 ataxia and Grade 2 tremors in the same patient. Most frequent treatment-related AEs were neutropenia and thrombocytopenia. Among 14 evaluable patients, one NSCLC patient showed partial response and 4 patients (one each with thyroid, prostatic, pancreatic carcinoma and peritoneal mesothelioma) showed long-term disease stabilization (>6-14 months). Pharmacokinetics of the orally administered milciclib (~t1/2 33 h) was not altered by concomitant treatment with gemcitabine.
CONCLUSIONS: The combination treatment was well tolerated with manageable toxicities. The recommended phase II dose was 80 mg/m2/day for milciclib and 1000 mg/m2/day for gemcitabine. This combination treatment regimen showed encouraging clinical benefit in ~36% patients, including gemcitabine refractory patients. These results support further development of combination therapies with milciclib in advanced cancer patients.

AT7519M is a small molecule inhibitor of cyclin-dependent kinases 1, 2, 4, 5, and 9 with in vitro activity against lymphoid malignancies. In two concurrent Phase II trials, we evaluated AT7519M in relapsed or refractory chronic lymphocytic leukemia (CLL) and mantle cell lymphoma (MCL) using the recommended Phase II dosing of 27 mg/m2 twice weekly for 2 of every 3 weeks. Primary objective was objective response rate (ORR). Nineteen patients were accrued (7 CLL, 12 MCL). Four CLL patients achieved stable disease (SD). Two MCL patients achieved partial response (PR), and 6 had SD. One additional MCL patient with SD subsequently achieved PR 9 months after completion of AT7519M. Tumor lysis syndrome was not reported. In conclusion, AT7519M was safely administered to patients with relapsed/refractory CLL and MCL. In CLL, some patients had tumor reductions, but the ORR was low. In MCL, activity was noted with ORR of 27%.