Phase 1 study of the MDM2 antagonist RO6839921 in patients with acute myeloid leukemia.

In acute myeloid leukemia (AML), TP53 mutations and dysregulation of wild-type p53 is common and supports an MDM2 antagonist as a therapy. RO6839921 is an inactive pegylated prodrug of the oral MDM2 antagonist idasanutlin (active principle [AP]) that allows for IV administration. This phase 1 monotherapy study evaluated the safety, pharmacokinetics, and pharmacodynamics of RO6839921 in patients with AML. Primary objectives identified dose-limiting toxicities (DLTs) and maximum tolerated dose (MTD). Secondary objectives assessed pharmacokinetic, pharmacodynamic, and antileukemic activity. A total of 26 patients received 120-300 mg AP of idasanutlin. The MTD was 200 mg, with DLTs at 250 (2/8 patients) and 300 mg (2/5). Treatment-related adverse events in >20% of patients were diarrhea, nausea, vomiting, decreased appetite, and fatigue. Six deaths (23.1%) occurred, all unrelated to treatment. Pharmacokinetics showed rapid and near-complete conversion of the prodrug to AP and dose-proportional exposure across doses. Variability ranged from 30%-47% (22%-54% for idasanutlin). TP53 was 21 (87.5%) wild-type and 3 mutant (12.5%). The composite response rate (complete remission [CR], CR with incomplete hematologic recovery/morphological leukemia-free state [CRi/MLFS], or CR without platelet recovery [CRp]) was 7.7%. Antileukemic activity (CR, CRi/MLFS, partial response, hematologic improvement/stable disease) was observed in 11 patients (disease control rate, 42%): 10/11 were TP53 wild-type; 1 had no sample. p53 activation was demonstrated by MIC-1 induction and was associated with AP exposure. There was not sufficient differentiation or improvement in the biologic or safety profile compared with oral idasanutlin to support continued development of RO6839921. NCT02098967.

A phase 1 study of the MDM2 antagonist RO6839921, a pegylated prodrug of idasanutlin, in patients with advanced solid tumors.

Purpose MDM2 is a negative regulator of the tumor suppressor p53. RO6839921 is an inactive pegylated prodrug of idasanutlin, an MDM2 antagonist, developed for intravenous administration. On cleavage by plasma esterases, the active principle (AP = idasanutlin) is released. This phase 1 study investigated the safety, pharmacokinetics, and pharmacodynamics of RO6839921 in patients with advanced solid tumors (NCT02098967). Methods Patients were evaluated on a 5-day dosing schedule every 28 days. Dose escalation used the Bayesian new continual reassessment model. Accelerated dose titration was permitted until grade ≥2 drug-related AEs were observed. The target DLT rate to define the MTD was 16-25%. p53 activation was assessed by measuring macrophage inhibitory cytokine-1 (MIC-1). Results Forty-one patients received 14-120 mg AP; 39 were DLT evaluable. The MTD was 110-mg AP (8% DLT rate), whereas 120-mg AP had a 44% DLT rate. DLTs were neutropenia, thrombocytopenia, and stridor. The most common treatment-related AEs (≥30%) were nausea, fatigue, vomiting, and thrombocytopenia. Pharmacokinetic analyses indicated rapid conversion of prodrug to AP and an approximately linear and dose-proportional dose-exposure relationship, with a 2-fold increase in exposure between Days 1 and 5 of AP. MIC-1 increases were exposure dependent. Stable disease was observed in 14 patients (34%). Conclusions RO6839921 showed reduced pharmacokinetic exposure variability and a safety profile comparable with that of oral idasanutlin. Although this study indicated that RO6839921 could be administered to patients, the results did not provide sufficient differentiation or improvement in the biologic or safety profile compared with oral idasanutlin to support continued development.

Evidence of a drug-drug interaction linked to inhibition of ester hydrolysis by orlistat.

: Orlistat, a lipase inhibitor taken with meals at doses of 60 mg (available over-the-counter) or 120 mg (prescription only) for treatment of obesity, is known to impair the absorption of fat-soluble molecules. Dalcetrapib, a modulator of cholesteryl ester transfer protein activity, is a lipophilic thioester prodrug. Lipase-induced and pancreatin-induced hydrolysis of dalcetrapib in biorelevant media in vitro was very efficiently inhibited by orlistat. Thus, the potential for orlistat to affect the bioavailability of concomitantly administered dalcetrapib was studied in an open-label 2-cohort study in 24 healthy volunteers as follows: single 600-mg doses of dalcetrapib were administered with increasing doses of orlistat (cohort A: 10, 40, 120 mg; cohort B: 20, 60, 120 mg). Exposure to the active form of dalcetrapib was more than 50% lower when taken with orlistat 60 mg or 120 mg than when taken alone. Similar trends were observed with lower orlistat doses (20 mg and 40 mg). Concomitant administration of orlistat also reduced the pharmacodynamic effects of dalcetrapib treatment on cholesteryl ester transfer protein activity. The interaction exceeds that predicted on the basis of dalcetrapib lipophilicity. These findings demonstrate the potential for large interactions between orlistat and esters that undergo de-esterification in the gastrointestinal tract, independent of lipophilicity.

Aleglitazar, a balanced PPARα/γ agonist, has no clinically relevant pharmacokinetic interaction with high-dose atorvastatin or rosuvastatin.

BACKGROUND: Aleglitazar, a dual PPAR-α/γ agonist, combines the lipid benefits of fibrates and the insulin-sensitizing benefits of thiazolidinediones. OBJECTIVE: To investigate the pharmacokinetic effects of co-administration of atorvastatin or rosuvastatin with aleglitazar. RESEARCH DESIGN AND METHODS: In a two-cohort, open-label, randomised, three-period crossover study, 44 healthy subjects received once-daily oral doses of aleglitazar 300 µg, statin (atorvastatin 80 mg or rosuvastatin 40 mg) and aleglitazar co-administered with each statin for 7 days. Plasma concentrations of each drug were measured and pharmacokinetic parameters determined on day 7 in each period. MAIN OUTCOME MEASURES: Peak observed plasma concentration (C(max)) and total exposures (AUC(0 - 24)) of aleglitazar, atorvastatin and rosuvastatin. RESULTS: C(max) and AUC(0 - 24) to aleglitazar were similar, whether administered alone or in combination with a statin. Total exposure to either statin was unaffected by co-administration with aleglitazar. C(max) treatment ratios for both statins exceeded the conventional no-effect boundary (1.25) when administered with aleglitazar. CONCLUSIONS: Co-administration of aleglitazar with a statin does not alter the pharmacokinetic profile of either drug.

No clinically relevant drug-drug interactions when dalcetrapib is co-administered with atorvastatin.

OBJECTIVES: Dalcetrapib, which targets cholesteryl ester transfer protein, is in clinical development for prevention of cardiovascular events and is likely to be used concomitantly with statins. Two studies investigated co-administration of dalcetrapib with atorvastatin and any effects of the timing of atorvastatin on the pharmacokinetics of dalcetrapib. RESEARCH DESIGN AND METHODS: Two crossover studies were performed in healthy subjects: a two-period study of dalcetrapib 900 mg concurrently with atorvastatin (concurrent dosing study) and a three-period study of dalcetrapib 600 mg (dose chosen for Phase III) with atorvastatin concurrently or serially 4 h after dalcetrapib (interval dosing study). MAIN OUTCOME MEASURES: The primary pharmacokinetic end points were AUC(0 - 24) and C(max); lipid effects and tolerability were secondary end points. RESULTS: In the concurrent study (n = 26), co-administration reduced dalcetrapib AUC(0 - 24) and C(max) and caused small changes in AUC(0 - 24) and C(max) of atorvastatin and its active metabolites. In the interval study (n = 52), serial and concurrent co-administration of atorvastatin resulted in similar reductions in dalcetrapib exposure that were comparable to those observed in the concurrent dosing study. Co-administration did not decrease the efficacy of dalcetrapib or atorvastatin and was generally well tolerated. CONCLUSIONS: These results indicate no clinically relevant interactions for co-administration of dalcetrapib with atorvastatin.

A prognostic index for systemic AIDS-related non-Hodgkin lymphoma treated in the era of highly active antiretroviral therapy.

BACKGROUND: The established International Prognostic Index for lymphomas has not included patients with systemic AIDS-related non-Hodgkin lymphoma. OBJECTIVE: To establish the most appropriate prognostic index for use in patients with systemic AIDS-related non-Hodgkin lymphoma. DESIGN: A prospective study involving univariate and multivariable analyses of patients with AIDS-related non-Hodgkin lymphoma whose data were used to examine standard and new criteria for survival after diagnosis. SETTING: The Chelsea and Westminster cohort of HIV-1-infected persons. PATIENTS: 9621 HIV-positive patients, 111 in whom AIDS-related non-Hodgkin lymphoma was treated after 1996, in the era of highly active antiretroviral therapy (HAART). INTERVENTION: Cox proportional hazards regression analysis to determine the prognostic significance of multiple clinicopathologic variables. RESULTS: Survival of patients with AIDS-related non-Hodgkin lymphoma has increased in the HAART era (log-rank chi-square, 9.23; P = 0.002). Univariate analyses using the established International Prognostic Index factors of age, tumor stage, lactate dehydrogenase level, Eastern Cooperative Oncology Group performance status, and number of extranodal sites were confirmed to be significant variables. Regression modeling for patients in whom disease was diagnosed after 1996 revealed only 2 independent predictors of death: International Prognostic Index risk group and CD4 cell count. These predictors yielded 4 internally validated risk strata with predicted 1-year survival rates of 82%, 47%, 20%, and 15% (P < 0.001). Prognostic risk scores in the highest quartile yielded a likelihood ratio for death of 7.90 (hazard ratio, 1.0), whereas a prognostic score less than 1.0 yielded a likelihood ratio of 0.23 (hazard ratio, 0.15 [95% CI, 0.06 to 0.33]). LIMITATIONS: The sample was small, and different HAART regimens were used. CONCLUSIONS: For patients with AIDS-related non-Hodgkin lymphoma that was diagnosed in the era of HAART, application of the International Prognostic Index remains useful. The addition of CD4 cell count provides further independent prognostic information. Patients who present with AIDS-related non-Hodgkin lymphoma and a low CD4 cell count have a poor prognosis; this information can be used to guide therapeutic options.

Hepatitis C infection is not associated with systemic HIV-associated non-Hodgkin's lymphoma: a cohort study.

Immunosuppression induced by the human immunodeficiency virus (HIV) increases the risk of developing non-Hodgkin's lymphoma (NHL). As the hepatitis C virus (HCV) has been implicated in the development of B cell lymphomas, we compared the incidence of systemic NHL during HIV infection compared to HIV and HCV co-infection. Of 5,832 individuals studied during the era of highly active anti-retroviral therapy (HAART), 102 patients were diagnosed with systemic NHL. The incidence of systemic NHL was 6.9 of 10(4) patient years during HIV infection compared to 7.1 of 10(4) patient years during HIV alone (p = 0.9). In this immunocompromised patient population, there was no association between HCV infection and an increased risk of lymphoma.

Protease inhibitors potentiate chemotherapy-induced neutropenia.

Pharmacokinetic interactions between chemotherapy and highly active antiretroviral therapy (HAART) are described, but there are few data on their clinical relevance. Patients with systemic AIDS-related non-Hodgkin lymphoma (ARL) were treated with concomitant HAART and infusional cyclophosphamide-doxorubicin-etoposide (CDE) chemotherapy. We compared neutropenia according to whether patients received protease inhibitor (PI)-based HAART or non-PI regimens. Differences in survival, response rates, immunologic parameters, and virologic parameters were also investigated. The day-10 (Mann-Whitney U test; P = .012) and day-14 (P = .025) neutrophil counts were significantly lower in patients receiving PIs, though there were no differences in the number of days of granulocyte colony-stimulating factor (G-CSF) administered between groups (P = .16). Grade 3 or 4 infections requiring hospitalization were recorded for a total of 58 (31%) of 190 cycles of CDE: 23 (48%) of 48 when prescribed PIs and 35 (25%) of 142 with concomitant PI-sparing HAART (chi(2) test; P = .0025). There were no statistically significant differences in the response rates, relapse-free survival, or disease-free survival between patients receiving PIs and those not receiving PIs. PI-based HAART appears to significantly potentiate the myelotoxicity of CDE chemotherapy. This potentiation may be a consequence of microsomal enzyme inhibition reducing the metabolism of cytotoxics in this regimen.