Increased bleeding risk associated with concurrent vascular endothelial growth factor receptor tyrosine kinase inhibitors and low-molecular-weight heparin.

BACKGROUND: Some cancer patients who are diagnosed with thromboembolism may require dual treatment with vascular endothelial growth factor receptor (VEGFR) tyrosine kinase inhibitors (TKIs) and factor Xa inhibitors (low-molecular-weight heparin [LMWH] or direct oral anticoagulants [DOACs]). However, to the authors' knowledge, the safety of such combinations has not been well characterized. METHODS: Patients with advanced cancer who were treated with concurrent VEGFR TKIs and factor Xa inhibitors between 2010 and 2018 at The Ohio State University Comprehensive Cancer Center were included. Charts were reviewed retrospectively for clinically significant bleeding events occurring during concurrent treatment compared with those occurring during factor Xa inhibitor therapy alone, using each patient as their own control. The Fisher exact test was used to compare distribution of bleeding severities. The Cox proportional hazards model was used to compare bleeding risk between groups. RESULTS: Among 86 patients, there were 29 clinically significant bleeding events (including 8 major bleeding events) reported during concurrent treatment and 17 events (including 4 major bleeding events) reported during factor Xa inhibitor therapy alone over a median follow-up of 63 days. Concurrent treatment was associated with significantly higher risks of overall bleeding (hazard ratio, 2.45; 95% confidence interval, 1.28-4.69 [P = .007]) and first-onset bleeding (hazard ratio, 2.23; 95% confidence interval, 1.13-4.42 [P = .02]). Analysis of 6-month bleeding risk and the subgroups of patients treated with concurrent TKIs and LMWH versus LMWH alone demonstrated a similar trend. The sample size was inadequate for comparisons between treatment with concurrent TKIs and DOACs versus DOACs alone. CONCLUSIONS: Concurrent treatment with VEGFR TKIs and LMWH was found to be associated with a significantly increased risk of bleeding events when compared with LMWH therapy alone.

Pemetrexed plus gemcitabine as first-line chemotherapy for patients with peritoneal mesothelioma: final report of a phase II trial.

PURPOSE: Pemetrexed in combination with cisplatin is approved for the treatment of pleural mesothelioma and is active in malignant peritoneal mesothelioma (MPeM). Pemetrexed and gemcitabine are synergistic in preclinical models, but the activity of this combination in MPeM is unknown. This clinical study assessed safety and efficacy of pemetrexed plus gemcitabine in chemotherapy-naïve patients with MPeM. PATIENTS AND METHODS: Treatment consisted of gemcitabine 1,250 mg/m(2) on days 1 and 8, and pemetrexed 500 mg/m(2) on day 8, administered immediately before gemcitabine. Treatment was repeated every 21 days for six cycles or until disease progression. All patients received folic acid, vitamin B(12), and dexamethasone supplementation. End points included tumor response, toxicity, time to disease progression (TTPD), and overall survival (OS). Disease control rate (DCR) was also calculated. RESULTS: Twenty patients were enrolled between December 2002 and May 2004. The confirmed response rate was 15% (95% CI, 3.2% to 37.9%), with three patients experiencing a partial response. The DCR was 50% (95% CI, 27.2% to 72.8%). The most common grade 3 to 4 nonhematologic toxicities included fatigue (20%), constipation (10%), vomiting (10%), and dehydration (10%). Hematologic toxicities included grade 3 to 4 neutropenia (60%) and febrile neutropenia (10%). One patient death was attributed to treatment. Median TTPD and OS times were 10.4 months and 26.8 months, respectively. CONCLUSION: The combination of pemetrexed plus gemcitabine was active in patients with MPeM with a notably high incidence of neutropenia. Median TTPD and OS seem promising. This regimen may provide an alternative to standard therapies, especially for patients who cannot tolerate a platinum-based regimen.

Safety and efficacy of transfusions of autologous cryopreserved platelets derived from recombinant human thrombopoietin to support chemotherapy-associated severe thrombocytopenia: a randomised cross-over study.

BACKGROUND: The increasing demand for platelet products, and concern over the transfusion-associated risks of alloimmunisation and infections, have motivated a search for improved methods aimed at keeping exposure to donor antigens to a minimum. Transfusion of thrombopoietin-derived autologous platelets might provide an alternative strategy. We aimed to compare the safety and efficacy of this strategy with that of transfusion with fresh allogeneic platelets in patients with severe chemotherapy-induced thrombocytopenia. METHODS: 20 patients with gynaecological malignancies were treated with two doses of 1.2 microg/kg recombinant human thrombopoietin. From day 12, we aimed to collect 50 units of platelets from these patients by plateletpheresis. Harvested platelets were cryopreserved in ThromboSol and 2% dimethyl sulfoxide (DMSO) for use in subsequent autologous transfusions. Patients then received carboplatin for up to six cycles. Patients were randomly assigned to group A (n=10), which received allogeneic fresh platelets at the first instance of severe thrombocytopenia (platelet count <15,000/microL) and then autologous cryopreserved platelets at the next, or to group B (n=10), which received first autologous and then allogeneic platelets. In subsequent cycles, all patients received autologous platelets while available. The primary endpoint was platelet count increment corrected for the number of platelets transfused and the patients' body-surface area. Analysis was by intention to treat. FINDINGS: Treatment with recombinant human thrombopoietin significantly increased platelet count (median 2.3-fold [range 1.5-3.3], p<0.0001) in all but one patient in group A. The median number of platelets collected per patient was 53 units (14-66) in two collections (one to three). There was no significant difference in the corrected platelet count increments (CCIs) between the 19 paired transfusions of cryopreserved autologous platelets and fresh allogeneic platelets (median 1-h CCI 15.7 vs 19.8, p=0.398; median 24-h CCI 13.0 vs 18.1, p=0.398). 14 of the 19 patients had a good response (1-h CCI >7.5) to their first transfusion of allogeneic platelets. By contrast, all patients had a good response to their first transfusion of autologous platelets (p=0.063). Moreover, no significant decrease in the CCIs (p=0.405) was seen over six cycles after autologous platelet transfusions (n=63). No transfusion reactions or any serious adverse event was recorded during autologous platelet transfusions. INTERPRETATION: Recombinant human thrombopoietin facilitated collection of multiple units of platelets, which could be cryopreserved and reinfused to counteract severe thrombocytopenia during multicycle chemotherapy. Transfusion of autologous cryopreserved platelets derived from recombinant human thrombopoietin can provide a viable strategy to minimise the risks of allogeneic platelet transfusions and provide a long-lasting supply of platelet support.