Phase Ib Trial With Birabresib, a Small-Molecule Inhibitor of Bromodomain and Extraterminal Proteins, in Patients With Selected Advanced Solid Tumors.

PURPOSE: Birabresib (MK-8628/OTX015) is a first-in-class bromodomain inhibitor with activity in select hematologic tumors. Safety, efficacy, and pharmacokinetics of birabresib were evaluated in patients with castrate-resistant prostate cancer, nuclear protein in testis midline carcinoma (NMC), and non-small-cell lung cancer in this phase Ib study. PATIENTS AND METHODS: Forty-seven patients were enrolled to receive birabresib once daily at starting doses of 80 mg continuously (cohort A) or 100 mg for 7 consecutive days (cohort B) in 21-day cycles using a parallel dose escalation 3 + 3 design. The primary objective was occurrence of dose-limiting toxicities (DLTs) and determination of the recommended phase II dose. RESULTS: Of 46 treated patients, 26 had castrate-resistant prostate cancer, 10 NMC, and 10 non-small-cell lung cancer. For cohort A, four of 19 (21%) evaluable patients had DLTs at 80 mg once daily (grade 3 thrombocytopenia [n = 3], ALT/hyperbilirubinemia [n = 1]) and two of three had DLTs at 100 mg once daily (grade 2 anorexia and nausea with treatment delay > 7 days [n = 1], grade 4 thrombocytopenia [n = 1]). No DLTs occurred in cohort B. Of 46 patients, 38 (83%) had treatment-related adverse events (diarrhea, 17 [37%]; nausea, 17 [37%]; anorexia, 14 [30%]; vomiting, 12 [26%]; thrombocytopenia 10 [22%]). Three patients with NMC (80 mg once daily) had a partial response (Response Evaluation Criteria in Solid Tumors [RECIST] version 1.1) with duration of 1.4 to 8.4 months. Pharmacokinetic analysis indicated a dose-proportional increase in birabresib exposure and rapid absorption. CONCLUSION: The recommended phase II dose of birabresib in patients with select solid tumors is 80 mg once daily with continuous dosing. Birabresib has dose-proportional exposure and a favorable safety profile, with clinical activity observed in NMC. Future studies of birabresib must consider intermittent scheduling to possibly mitigate the toxicities of chronic dosing.

Phase I trial of volasertib, a Polo-like kinase inhibitor, plus platinum agents in solid tumors: safety, pharmacokinetics and activity.

BACKGROUND: This trial evaluated the maximum tolerated dose (MTD), safety, pharmacokinetics, and activity of volasertib, a selective Polo-like kinase 1 inhibitor that induces mitotic arrest and apoptosis, combined with cisplatin or carboplatin in patients with advanced/metastatic solid tumors (NCT00969761; 1230.6). METHODS: Sequential patient cohorts (3 + 3 dose-escalation design) received a single infusion of volasertib (100-350 mg) with cisplatin (60-100 mg/m(2)) or carboplatin (area under the concentration versus time curve [AUC]4-AUC6) on day 1 every 3 weeks for up to six cycles. Sixty-one patients received volasertib/cisplatin (n = 30) or volasertib/carboplatin (n = 31) for a median of 3.5 (range, 1-6) and 2.0 (range, 1-6) treatment cycles, respectively. RESULTS: The most common cycle 1 dose-limiting toxicities (DLTs) were thrombocytopenia, neutropenia and fatigue. MTDs (based on cycle 1 DLTs) were determined to be volasertib 300 mg plus cisplatin 100 mg/m(2) and volasertib 300 mg plus carboplatin AUC6. Co-administration did not affect the pharmacokinetics of each drug. Partial responses were observed in two patients in each arm. Stable disease was achieved in 11 and six patients treated with volasertib/cisplatin and volasertib/carboplatin, respectively. CONCLUSIONS: Volasertib plus cisplatin or carboplatin at full single-agent doses was generally manageable and demonstrated activity in heavily pretreated patients with advanced solid tumors.

Eribulin mesylate in the management of metastatic breast cancer and other solid cancers: a drug review.

In the new era of 'precision' cancer medicine, new drug development has shifted from cytotoxic chemotherapy to molecularly targeted agents. Eribulin mesylate, a microtubule-destabilizing agent, is the only 'classical' cytotoxic agent approved for the treatment of breast cancer in the last 7 years. This synthetic analogue of halichondrin B, isolated from the marine sponge 'Halicondria Okaida', was responsible for prolonging overall survival of heavily pretreated metastatic breast cancer patients in a large Phase III trial. Eribulin is now under clinical development in earlier settings such as the neo-adjuvant and adjuvant settings. Furthermore, its unique mechanism of action and the absence of cross-resistance with taxanes have led to the design of clinical trials in multiple indications: bladder cancer, lung cancer, prostate cancer… The main adverse events are neutropenia, fatigue and peripheral neuropathy.

Breast cancer, DPYD mutations and capecitabine-related ileitis: description of two cases and a review of the literature.

Despite many treatment advances, metastatic breast cancer remains an incurable disease and is the third leading cause of cancer-related deaths in Europe. Capecitabine has become a standard treatment option for metastatic breast cancer, as a single agent or in combination. Hand-foot syndrome and diarrhoea are the most frequently reported side effects, while capecitabine-related ileitis is very rare. Deficiency of dihydropyrimidine dehydrogenase activity leads to severe toxicities after administration of 5-fluorouracil or its prodrugs. We report two cases of patients with metastatic breast cancer who developed ileitis after treatment with capecitabine. One patient had a DPYD gene abnormality.

Molecular biology in medical oncology: diagnosis, prognosis, and precision medicine.

Biomarkers may have prognostic and/or predictive value and have relied mainly on clinico-pathological information. Prognostic biomarkers provide information on patients' outcome irrespective of treatment, whereas predictive biomarkers provide information on the likelihood of response to a specific therapy. Biomarkers in the treatment of solid tumors were determined for many decades on protein expression by immunohistochemistry. Over the last decade, microarray-based technologies and new high-throughput sequencing methods have emerged, leading to a better understanding of tumor biology. The landmark advances in tumor genomics have highlighted specific molecular abnormalities, such as copy number alterations, mutations, and rearrangements. Several new cancer drugs target those specific molecular alterations or cell signaling pathways yielding unprecedented anti-cancer activity. Gene expression signatures have been developed in order to tailor adjuvant treatment in common tumor types. The "one size fits all" approach has been replaced by a personalized approach. The advent of massive parallel sequencing is responsible of a paradigm shift in biomarker discovery and clinical trial design on the way to what is now called "biomarker-driven cancer medicine" or "precision medicine."

Sequential use of protein kinase inhibitors potentiates their toxicity to melanoma cells: a rationale to combine targeted drugs based on protein expression inhibition profiles.

Targeted therapy has shown high efficacy in the treatment of metastatic melanoma with impressive response rates. However, resistance appears after a few months, underlining the need for simultaneous multiple signalling pathway inhibition to provide a durable benefit. The aim of our study was to evaluate the possible synergistic effect of various protein kinase inhibitor combinations targeting SRC, MEK, PI3K or JAK on the survival of representative melanoma cell lines with WTNRAS/WTBRAF and harbouring the most frequent mutations (Q61LNRAS/WTBRAF or WTNRAS/V600EBRAF). By comparing IC50s and protein inhibition profiles, cell exposure to a single inhibitor for 3 days (condition 1) showed that both WTBRAF lines were at least 15-fold more sensitive to SRC inhibition while V600EBRAF cells were 30-fold more sensitive to MEK inhibition, confirming that the latter cells are largely dependent on the MAPK pathway for growth. Concomitant treatment for 3 days (condition 2) revealed an antagonistic effect between SRC and JAK inhibitors as compared to treatment by each inhibitor alone in all 3 lines, supporting that both SRC and JAK stimulate the STAT pathway. Finally, sequential cell exposure to inhibitors by pre-treatment with a single effector at non-toxic but effective on target inhibition concentrations for 7 days followed by the addition of each of the other inhibitors for 3 days (condition 3) showed that MEK, PI3K or JAK inhibitor acted in synergy with the SRC inhibitor in both wild-type and Q61LNRAS cells, suggesting that the first inhibitor could activate the SRC/STAT compensatory signalling pathway. In conclusion, a treatment strategy consisting in a sequential use of targeted inhibitors to first render melanoma cells more dependent on alternative compensatory pathways that should subsequently be inhibited, may enhance efficacy. By contrast, concomitant exposure to various combinations of inhibitors at different concentrations failed to produce such effect, further supporting the importance of both the duration of cell exposure to inhibitors and their sequential use.

Targeted therapies of solid cancers: new options, new challenges.

PURPOSE OF REVIEW: The landscape of medical oncology is filled with approvals of new anticancer agents, the majority of which are targeted agents. This shift in therapies raises multiple challenges including the appearance of new toxicities, the need for biomarkers, the emergence of genomics and the evolution of cancer molecular imaging. RECENT FINDINGS: Biopsy of metastatic lesions is slowly becoming a standard of care before the initiation of any therapy. These invasive procedures have been found to be generally well tolerated and are being put to use with the emergence of genomics. Gene sequencing and new imaging techniques are serving the understanding of tumor biology and the search for 'biomarkers' predicting response and resistance to treatment. New clinical trial designs incorporating the 'presumed' biomarkers are guiding patients to specific treatments and have shown outcome improvements. SUMMARY: Many questions remain however unanswered and new challenges appear. Intratumor heterogeneity emerges as a brake to personalized cancer care. Relevant targets remain undruggable and costs may hinder progress. Furthermore, technical issues continue to arise. The ultimate goal remains to achieve cure by blocking the multiple pathways of cancer development and proliferation, while sparing the patients the burden of therapy.

Adjuvant chemo-radiation for gastric adenocarcinoma: an institutional experience.

BACKGROUND: Studies have shown that surgery alone is less than satisfactory in the management of early gastric cancer, with cure rates approaching 40%. The role of adjuvant therapy was indefinite until three large, randomized controlled trials showed the survival benefit of adjuvant therapy over surgery alone. Chemoradiation therapy has been criticized for its high toxicity. METHODS: 24 patients diagnosed between September 2001 and July 2007 were treated with adjuvant chemoradiation. 18 patients had the classical MacDonald regimen of 4500 cGy of XRT and chemotherapy with 5-fluorouracil (5FU) and leucovorin, while chemotherapy consisted of 5FU/Cisplatin for 6 patients. RESULTS: This series consisted of non-metastatic patients, 17 females and 7 males with a median age of 62.5 years. 23 patients (96%) had a performance status of 0 or 1. The full course of radiation therapy (4500 cGy) was completed by 22 patients (91.7%). Only 7 patients (36.8%) completed the total planned courses of chemotherapy. 2 local relapses (10%), 2 regional relapses (10%) and 2 distant relapses (10%) were recorded. Time to progression has not been reached. 9 patients (37.5%) died during follow-up with a median overall survival of 75 months. Patients lost a mean of 4 Kgs during radiation therapy. We recorded 6 episodes of febrile neutropenia and the most frequent toxicity was gastro-intestinal in 17 patients (70.8%) with 9 (36%) patients suffering grade 3 or 4 toxicity and 5 patients (20%) suffering from grade 3 or 4 neutropenia. 4 (17%) patients required total parenteral nutrition for a mean duration of 20 days. 4 patients suffered septic shock (17%) and 1 patient developed a deep venous thrombosis and a pulmonary embolus. CONCLUSIONS: Adjuvant chemo-radiation for gastric cancer is a standard at our institution and has resulted in few relapses and an interesting median survival. Toxicity rates were serious and this remains a harsh regimen with only 36.8% of patients completing the full planned courses of chemotherapy. This is due to hematological toxicity, mainly febrile neutropenia. This should prompt us to review the subsequent chemotherapy protocol and make it more tolerable.