Application of population physiologically based pharmacokinetic modelling to optimize target expression and clearance mechanisms of therapeutic monoclonal antibodies.

AIMS: To use population physiologically based pharmacokinetic (PopPBPK) modelling to optimize target expression, kinetics and clearance of HER1/2 directed therapeutic monoclonal antibodies (mAbs). Thus, to propose a general workflow of PopPBPK modelling and its application in clinical pharmacology. METHODS: Full PBPK model of pertuzumab (PTZ) was developed in patient population using Simcyp V21R1 incorporating mechanistic targeted-mediated drug disposition process by fitting known clinical PK and sparse receptor proteomics data to optimize target expression and kinetics of HER2 receptor. Trastuzumab (TTZ) PBPK modelling was used to validate the optimized HER2 target. Additionally, the simulator was also used to develop a full PBPK model for the HER1-directed mAb cetuximab (CTX) to assess the underlying targeted-mediated drug disposition-independent elimination mechanisms. RESULTS: HER2 final parameterisation coming from the PBPK modelling of PTZ was successfully cross validated through PBPK modelling of TTZ with average fold error (AFE), absolute AFE and percent prediction error values for area under the concentration-time curve (AUC) and maximum plasma concentration (Cmax ) of 1.13, 1.16 and 16, and 1.01, 1.07 and 7, respectively. CTX PBPK model performance was validated after the incorporation of an additional systemic clearance of 0.033 L/h as AFE and absolute AFE showed an acceptable predictive power of AUC and Cmax with percent prediction error of 13% for AUC and 10% for Cmax . CONCLUSIONS: Optimisation of both system and drug related parameters were performed through PBPK modelling to improve model performance of therapeutic mAbs (PTZ, TTZ and CTX). General workflow was proposed to develop and apply PopPBPK to support clinical development of mAbs targeting same receptor.

Quantitative determination of lurbinectedin, its unbound fraction and its metabolites in human plasma utilizing ultra-performance LC-MS/MS.

AIMS: Ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) methods to quantify total lurbinectedin, its plasma protein binding to derive the unbound fraction and its main metabolites 1',3'-dihydroxy-lurbinectedin (M4) and N-desmethyl-lurbinectedin (M6) in human plasma, were developed and validated. MATERIALS & METHODS: For lurbinectedin, sample extraction was performed using supported liquid extraction. For metabolites, liquid-liquid extraction with stable isotope-labeled analogue internal standards was used. Plasma protein binding was evaluated using rapid equilibrium dialysis. In vitro investigations at different plasma protein concentrations were carried out to estimate dissociation rate constants to albumin and alpha-1-acid glycoprotein (AAG). RESULTS: Calibration curves displayed good linearity over 0.1 to 50 ng/mL for lurbinectedin and 0.5 to 20 ng/mL for the metabolites. Methods were validated in accordance with established guidance. The inter-day precision and accuracy ranged from 5.1% to 10.7%, and from -5% to 6% (lurbinectedin in plasma); from 3.1% to 6.6%, and from 4% to 6% (lurbinectedin in plasma:PBS); from 4.5% to 12.9%, and from 4% to 9% (M4); and from 7.5% to 10.5%, and from 6% to 12% (M6). All methods displayed good linearity (r2 >0.99). Recovery was evaluated for lurbinectedin in plasma:PBS (66.4% to 86.6%), M4 (7.82% to 13.4%) and M6 (22.2% to 34.3%). The method for lurbinectedin in plasma has been applied in most clinical studies, while the plasma:PBS and metabolites methods were used to evaluate the impact of special conditions on lurbinectedin PK. Lurbinectedin plasma protein binding was 99.6% and highly affected by AAG concentration. CONCLUSIONS: These UPLC-MS/MS methods enable the rapid and sensitive quantification of lurbinectedin and its main metabolites in clinical samples.

Determining What Represents Value in the Treatment of Refractory or Unexplained Chronic Cough from the Perspective of Key Stakeholders in Spain Using Multi-Criteria Decision Analysis.

BACKGROUND AND OBJECTIVE: Chronic cough is defined as cough lasting for more than 8 weeks. It can be described as refractory when persisting despite thorough clinical assessment and treatment of any cough-related underlying condition, or unexplained when no underlying cough-related condition can be identified. Refractory or unexplained chronic cough (RCC|UCC) greatly affects patient health-related quality of life (HRQoL). Although around 10% of the population suffer from chronic cough (with 40-60% of these patients suffering from RCC|UCC), there is limited information available in the literature about the condition and the assessment of treatment success. This study aimed to determine what represents value in the treatment of RCC|UCC from the perspective of key stakeholders in Spain using Multi-Criteria Decision Analysis (MCDA) methodology. METHODS: A literature review was conducted to adapt the MCDA framework to the specific context of RCC|UCC. A total of 24 participants were involved, representing three key stakeholder groups (7 patients, 9 physicians and 8 hospital pharmacists). The study was structured in two phases. In Phase 1, participants validated the adapted MCDA framework and assigned relative weights (100-point allocation) to the framework's value criteria/sub-criteria during three individual stakeholder meetings, one per each stakeholder group. In Phase 2, participants were brought together in a multi-stakeholder meeting to review findings of each stakeholder group, after which stakeholders repeated the weighting exercise as a collective group. All meetings included reflective discussion by participants of each value criteria/sub-criteria included within the adapted MCDA framework, where stakeholders shared their perspectives and opinions on what represents value in RCC|UCC. RESULTS: Refractory or unexplained chronic cough is regarded as a chronic medical condition, with variable severity across patients and the potential to heavily impact their HRQoL (including physical, psychological and social/work productivity domains). Current treatments used by healthcare professionals, which have not been specifically developed and are not approved for RCC|UCC, show limited clinical effectiveness and associated safety and tolerability issues, which result in frequent treatment discontinuations. The reduction of the average cough frequency over a 24-h period is regarded as the primary goal of treatment by stakeholders, with the aim of improving HRQoL. Improvement of other cough symptoms, such as intensity, is also considered important. Minor adverse events and a slower onset of treatment effect would be acceptable to stakeholders if accompanied by strong efficacy and improvement in HRQoL. Given the inability to measure cough frequency in clinical practice, Patient-Reported Outcomes (PROs) could be considered a proxy of treatment effectiveness. A multidisciplinary approach to the condition is regarded as key for treatment success. CONCLUSIONS: Refractory or unexplained chronic cough is a medical condition that seriously impacts patients' HRQoL. The primary goal of treatment is to improve patients' HRQoL by reducing the frequency and intensity of cough.

A Phase I Study of Capivasertib in Combination With Abiraterone Acetate in Patients With Metastatic Castration-Resistant Prostate Cancer.

BACKGROUND: Although androgen receptor-targeted agents prolong the lives of patients with metastatic prostate cancer, patients develop therapy resistance and most ultimately succumb to the disease. The PI3K/AKT/PTEN pathway has been associated with the development of resistance, raising the possibility that pathway inhibitors may produce a clinical benefit. This open-label phase Ib study examined the safety, tolerability, pharmacokinetics (PK) and preliminary clinical activity of adding capivasertib - a potent, selective inhibitor of AKT1/2/3 - to approved abiraterone acetate therapy. METHODS: Twenty-seven patients with metastatic castration-resistant prostate cancer who had undergone at least 1 prior line of systemic therapy received abiraterone acetate 1000 mg (orally administered once daily), plus oral prednisone 5 mg (twice daily) with capivasertib 400 mg (orally, twice daily, with an intermittent schedule of 4 days on, 3 days off). RESULTS: No dose-limiting toxicity was observed. The most frequent adverse events (all grade) were diarrhea (30%), anemia (26%), asthenia (22%), and nausea (22%). The most frequent grade 3 or higher adverse events were acute kidney injury (19%), hyperglycemia (7%), rash (7%), abdominal pain (7%), and asthenia (7%). Capivasertib and abiraterone PK were consistent with previously reported results from monotherapy dosing. Nine participants (33%) showed a 20% or greater decrease in prostate-specific antigen during study treatment. CONCLUSION: The combination of capivasertib and abiraterone acetate had an acceptable tolerability profile consistent with the known profile of each agent. These data support further evaluation of capivasertib and abiraterone acetate in patients with advanced prostate cancer.

Phase I study of lurbinectedin in combination with weekly paclitaxel with or without bevacizumab in patients with advanced solid tumors.

Lurbinectedin and paclitaxel showed synergism in preclinical studies and have non-completely overlapping toxicity profiles. This phase I trial evaluated a combination of paclitaxel and lurbinectedin with/without bevacizumab in advanced tumors. This trial was divided into Group A, which evaluated weekly paclitaxel (60 or 80 mg) plus lurbinectedin (3.0-5.0 mg flat dose [FD] or 2.2 mg/m2) every 3 weeks in advanced solid tumors; and Group B, which evaluated bevacizumab (BEV, 15 mg/kg) added to the recommended dose (RD) defined in Group A in advanced epithelial ovarian or non-small cell lung cancer (NSCLC). 67 patients (A, n = 55; B, n = 12) were treated. The RD was paclitaxel 80 mg/m2 on Day (D)1,D8 plus lurbinectedin 2.2 mg/m2 on D1. At this RD, myelotoxicity was reversible and manageable, and most non-hematological toxicities were mild/moderate. Adding BEV did not notably change tolerability. Twenty-five confirmed responses were observed: 20/51 evaluable patients in Group A (overall response rate [ORR] = 39% at all dose levels and at the RD), and 5/10 evaluable patients in Group B (ORR = 50%). Most responders had breast (n = 7/12 patients), small cell lung (SCLC) (n = 5/7), epithelial ovarian (n = 3/9) and endometrial cancer (n = 3/11) in Group A, and epithelial ovarian (n = 3/4) and NSCLC (n = 2/6) in Group B. Clinical benefit rate was 61% in Group A (58% at the RD), and 90% in Group B. No major pharmacokinetic drug-drug interactions were observed. Paclitaxel/lurbinectedin and paclitaxel/lurbinectedin/BEV are feasible combinations. Further development is warranted of paclitaxel/lurbinectedin in SCLC, breast, and endometrial cancer, and of paclitaxel/lurbinectedin/BEV in epithelial ovarian cancer.

Integrated exposure-response analysis of efficacy and safety of lurbinectedin to support the dose regimen in small-cell lung cancer.

PURPOSE: These exposure-response (E-R) analyses integrated lurbinectedin effects on key efficacy and safety variables in relapsed SCLC to determine the adequacy of the dose regimen of 3.2 mg/m2 1-h intravenous infusion every 3 weeks (q3wk). METHODS: Logistic models and Cox regression analyses were applied to correlate lurbinectedin exposure metrics (AUCtot and AUCu) with efficacy and safety endpoints: objective response rate (ORR) and overall survival (OS) in SCLC patients (n = 99) treated in study B-005 with 3.2 mg/m2 q3wk, and incidence of grade 4 (G4) neutropenia and grade 3-4 (G ≥ 3) thrombocytopenia in a pool of cancer patients from single-agent phase I to III studies (n = 692) treated at a wide range of doses. A clinical utility index was used to assess the appropriateness of the selected dose. RESULTS: Effect of lurbinectedin AUCu on ORR best fitted to a sigmoid-maximal response (Emax) logistic model, where Emax was dependent on chemotherapy-free interval (CTFI). Cox regression analysis with OS found relationships with both CTFI and AUCu. An Emax logistic model for G4 neutropenia and a linear logistic model for G ≥ 3 thrombocytopenia, which retained platelets and albumin at baseline and body surface area, best fitted to AUCtot and AUCu. AUCu between approximately 1000 and 1700 ng·h/L provided the best benefit/risk ratio, and the dose of 3.2 mg/m2 provided median AUCu of 1400 ng·h/L, thus maximizing the proportion of patients within that lurbinectedin target exposure range. CONCLUSIONS: The relationships evidenced in this integrated E-R analysis support a favorable benefit-risk profile for lurbinectedin 3.2 mg/m2 q3wk. TRIAL REGISTRATION: Clinicaltrials.gov: NCT02454972; registered May 27, 2015.

Long-term safety and efficacy study of a medical device containing xyloglucan, pea protein reticulated with tannins and xylo-oligosaccharides, in patients with diarrhoea-predominant irritable bowel syndrome.

BACKGROUND: Irritable bowel syndrome with diarrhoea (IBS-D) is a frequent problem associated with a significant socioeconomic implication. Increased gut permeability is an important pathophysiological mechanism. A medical device containing xyloglucan (XG), pea protein and tannins (PPT) from grape-seed extract, and xylo-oligosaccharides (XOS) has proven restoration of intestinal barrier function. Our objective was to evaluate the efficacy and safety of treatment with the medical device XG + PPT + XOS (XG-PPT-XOS) in adult patients with IBS-D in a clinical setting for 6 months. MATERIAL AND METHODS: This was a multicentre, open-label, prospective, observational study conducted to evaluate long-term safety and efficacy of XG-PPT-XOS. IBS-D adult patients (Rome IV criteria) were included and received two tablets twice daily for 6 months. IBS Symptom Severity Score (IBS-SSS) and bowel habit were registered at baseline and monthly, until the end of follow up. Efficacy was evaluated by comparison of mean scores at each time point. RESULTS: 50 patients were included, of which 19 completed the 6 months. IBS-SSS score decreased from 312.2 ± 82.2 to 213.6 ± 109.9 (p < 0.0001) at 1 month and 192.0 ± 108.9 at the last visit completed; diarrhoea score decreased from 45.6 ± 17.9 to 25.7 ± 17.7 and 25.3 ± 17.2 at 1 month and at the last visit completed, respectively. Pain score decreased from 107.8 ± 49.9 at baseline to 73.2 ± 57.3 (p < 0.0001) at 1 month and bloating score from 56.4 ± 28.8 at baseline to 42.8 ± 32.6 (p < 0.001) at 1 month, reaching 62.4 ± 56.0 and 40.4 ± 34.3, respectively, at the last visit completed. Adverse effects were mild and mostly not related to treatment. CONCLUSION: Treating IBS-D patients with XG-PPT-XOS is effective and safe in the long term within a clinical setting, improving all IBS-D symptoms from the first month of treatment and showing a sustained response over the term of therapy.

Population Pharmacokinetic-Pharmacodynamic Modeling and Covariate Analyses of Neutropenia and Thrombocytopenia in Patients With Solid Tumors Treated With Lurbinectedin.

Lurbinectedin is a selective inhibitor of oncogenic transcription. Reversible myelosuppression is its most relevant toxicity. Pharmacokinetic-pharmacodynamic analyses were conducted to characterize the time course of absolute neutrophil count and platelet count recovery and to detect and quantify the effect of relevant covariates in patients with advanced solid tumors treated with lurbinectedin. Absolute neutrophil count, platelet count, and lurbinectedin total plasma concentration were assessed in 244 patients treated with lurbinectedin with varied dosing schedules and doses. A reference extended semimechanistic pharmacokinetic-pharmacodynamic model of myelosuppression was used. Granulocyte colony-stimulating factor (G-CSF) administration was modeled as a dichotomous covariate, and platelet transfusions were included as a bolus dose into the last compartment of the model, representing the central circulation. Final models were suitable to describe the time course of absolute neutrophil count and platelet count recovery. A lurbinectedin dose of 3.2 mg/m2 every 3 weeks can be administered without primary prophylaxis with G-CSF. G-CSF followed by ≤2 dose reductions of 20%, if needed, gradually reduced grade 4 neutropenia from cycle 3 onward. BSA-based dosing reduced the incidence of grade ≥ 3 thrombocytopenia. One-week dose delays because of low absolute neutrophil count occurred in 3.5% of patients, thus supporting every-3-week administration. CYP3A inhibitors produced absolute 11.0% and 6.2% increases in grade ≥ 3 neutropenia and thrombocytopenia, respectively. Neutropenia and thrombocytopenia after lurbinectedin administration to cancer patients are noncumulative, reversible, short lasting, and clinically manageable with secondary prophylaxis of G-CSF or platelet transfusion and, if needed, dose reductions.

Effect of lurbinectedin on the QTc interval in patients with advanced solid tumors: an exposure-response analysis.

PURPOSE: This study assessed the effect of lurbinectedin, a highly selective inhibitor of oncogenic transcription, on the change from baseline in Fridericia's corrected QT interval (∆QTcF) and electrocardiography (ECG) morphological patterns, and lurbinectedin concentration-∆QTcF (C-∆QTcF) relationship, in patients with advanced solid tumors. METHODS: Patients with QTcF ≤ 500 ms, QRS < 110 ms, PR < 200 ms, and normal cardiac conduction and function received lurbinectedin 3.2 mg/m2 as a 1-h intravenous infusion every 3 weeks. ECGs were collected in triplicate via 12-lead digital recorder in treatment cycle 1 and 2 and analyzed centrally. ECG collection time-matched blood samples were drawn to measure lurbinectedin plasma concentration. No effect on QTc interval was concluded if the upper bound (UB) of the least square (LS) mean two-sided 90% confidence intervals (CI) for ΔQTcF at each time point was < 20 ms. C-∆QTcF was explored using linear mixed-effects analysis. RESULTS: A total of 1707 ECGs were collected from 39 patients (females, 22; median age, 56 years). The largest UB of the 90% CI of ΔQTcF was 9.6 ms, thus lower than the more conservative 10 ms threshold established at the ICH E14 guideline for QT studies in healthy volunteers. C-∆QTcF was better fit by an effect compartment model, and the 90% CI of predicted ΔQTcF at Cmax was 7.81 ms, also below the 10 ms threshold of clinical concern. CONCLUSIONS: ECG parameters and C-ΔQTcF modelling in this prospective study indicate that lurbinectedin was not associated with a clinically relevant effect on cardiac repolarization.

Population-Pharmacokinetic and Covariate Analysis of Lurbinectedin (PM01183), a New RNA Polymerase II Inhibitor, in Pooled Phase I/II Trials in Patients with Cancer.

BACKGROUND AND OBJECTIVES: Lurbinectedin is an inhibitor of RNA polymerase II currently under clinical development for intravenous administration as a single agent and in combination with other anti-tumor agents for the treatment of several tumor types. The objective of this work was to develop a population-pharmacokinetic model in this patient setting and to elucidate the main predictors to guide the late stages of development. METHODS: Data from 443 patients with solid and hematologic malignancies treated in six phase I and three phase II trials with lurbinectedin as a single agent or combined with other agents were included in the analysis. The potential influence of demographic, co-treatment, and laboratory characteristics on lurbinectedin pharmacokinetics was evaluated. RESULTS: The final population-pharmacokinetic model was an open three-compartment model with linear distribution and linear elimination from the central compartment. Population estimates for total plasma clearance, and apparent volume at steady state were 11.2 L/h and 438 L, respectively. Inter-individual variability was moderate for all parameters, ranging from 20.9 to 51.2%. High α-1-acid glycoprotein and C-reactive protein, and low albumin reduced clearance by 28, 20, and 20%, respectively. Co-administration of cytochrome P450 3A inhibitors reduced clearance by 30%. Combinations with other anti-tumor agents did not modify the pharmacokinetics of lurbinectedin significantly. CONCLUSION: The population-pharmacokinetic model indicated neither a dose nor time dependency, and no clinically meaningful pharmacokinetic differences were found when co-administered with other anticancer agents. A chronic inflammation pattern characterized by decreased albumin and increased C-reactive protein and α-1-acid glycoprotein levels led to high lurbinectedin exposure. Co-administration of cytochrome P450 3A inhibitors increased lurbinectedin exposure.

Phase I study of lurbinectedin, a synthetic tetrahydroisoquinoline that inhibits activated transcription, induces DNA single- and double-strand breaks, on a weekly × 2 every-3-week schedule.

Background Lurbinectedin administered as a 1-h intravenous infusion every 3 weeks induces neutropenia, with the nadir usually occurring during the second week. This phase I study evaluated an alternative lurbinectedin dosing schedule consisting of a 1-h infusion on days 1 and 8 every 3 weeks. Patients and methods Twenty-one patients with advanced cancer received lurbinectedin using a standard cohort dose escalation design. Results Three dose levels of 3, 4, and 5 mg of lurbinectedin were explored. The recommended phase II dose was 5 mg, with 3 of 13 patients having dose-limiting toxicity (DLT), although grade 4 neutropenia occurred in 50% of patients. Other frequent toxicities were mild to moderate nausea and vomiting, fatigue, decreased appetite, stomatitis and asymptomatic creatinine and transaminase increases. No objective responses occurred, but prolonged stable disease was observed in 7 patients, including 3 with soft tissue sarcoma. Conclusion The recommended phase II dose of lurbinectedin is 5 mg, administered as a 1-h infusion on days 1 and 8 every 3 weeks. These data support further testing of this dose and schedule, particularly in soft tissue sarcoma.

Phase I clinical and pharmacokinetic study of PM01183 (a tetrahydroisoquinoline, Lurbinectedin) in combination with gemcitabine in patients with advanced solid tumors.

Background To determine the recommended dose (RD) of a combination of PM01183 and gemcitabine in patients with advanced solid tumors. Methods Forty-five patients received escalating doses of PM01183/gemcitabine on Days 1 and 8 every 3 weeks (d1,8 q3wk) following a standard 3 + 3 design. Results PM01183 3.5 mg flat dose (FD)/gemcitabine 1000 mg/m2 was the highest dose level tested. Dose-limiting toxicities (DLTs) were mostly hematological and resulted in the expansion of a lower dose level (PM01183 3.5 mg FD/gemcitabine 800 mg/m2); 19 patients at this dose level were evaluable but >30% had DLT and >20% had febrile neutropenia. No DLT was observed in 11 patients treated at PM01183 3.0 mg FD/gemcitabine 800 mg/m2, which was defined as the RD. This regimen was feasible and tolerable with manageable toxicity; mainly grade 3/4 myelosuppression. Non-hematological toxicity comprised fatigue, nausea, vomiting, and transaminases increases. Fifteen (33%) patients received ≥6 cycles with no cumulative hematological toxicity. Pharmacokinetic analysis showed no evidence of drug-drug interaction. Nine of 38 patients had response as per RECIST (complete [3%] and partial [21%]), for an overall response rate (ORR) of 24% (95% Confidence Interval [CI] 12-40%). Eleven patients (29%) had disease stabilization ≥4 months. Responses were durable (median of 8.5 months): overall median progression-free survival (PFS) was 4.2 months (95% CI, 2.7-6.5 months). Conclusions The RD for this combination is PM01183 3.0 mg FD (or 1.6 mg/m2)/gemcitabine 800 mg/m2 d1,8 q3wk. This schedule is well tolerated and has antitumor activity in several advanced solid tumor types.

Diagnosis and management of functional symptoms in inflammatory bowel disease in remission.

Inflammatory bowel disease (IBD) patients in remission may suffer from gastrointestinal symptoms that resemble irritable bowel syndrome (IBS). Knowledge on this issue has increased considerably in the last decade, and it is our intention to review and summarize it in the present work. We describe a problematic that comprises physiopathological uncertainties, diagnostic difficulties, as IBS-like symptoms are very similar to those produced by an inflammatory flare, and the necessity of appropriate management of these patients, who, although in remission, have impaired quality of life. Ultimately, from almost a philosophical point of view, the presence of IBS-like symptoms in IBD patients in remission supposes a challenge to the traditional functional-organic dichotomy, suggesting the need for a change of paradigm.

Gastroesophageal reflux as a cause of chronic cough, severe asthma, and migratory pulmonary infiltrates.

Gastroesophageal reflux (GER), asthma-type cough and upper airway disease are the most common causes of chronic cough syndrome. We present a case in which impedance-pH monitoring indicated severe mixed acid-nonacid esophageal reflux reaching the upper third of the esophagus in 75% of nonacid events. GER and the associated aspiration episodes were shown to be the cause of severe asthma attacks and migratory pulmonary infiltrates. GER was caused by a sleeve gastrectomy, which seriously disabled the mechanisms preventing reflux from reaching the airways. Respiratory symptoms improved notably after abdominal surgery to correct the GER, suggesting a close causal relationship between GER and all the symptoms, including asthma. However, this issue remains unresolved in the literature.

First-in-human phase I study of Lurbinectedin (PM01183) in patients with advanced solid tumors.

PURPOSE: Lurbinectedin (PM01183) binds covalently to DNA and has broad activity against tumor cell lines. This first-in-human phase I study evaluated dose-limiting toxicities (DLT) and defined a phase II recommended dose for PM01183 as a 1-hour intravenous infusion every three weeks (q3wk). EXPERIMENTAL DESIGN: Thirty-one patients with advanced solid tumors received escalating doses of PM01183 following an accelerated titration design. RESULTS: PM01183 was safely escalated over 200-fold, from 0.02 to 5.0 mg/m(2). Dose doubling was utilized, requiring 15 patients and nine dose levels to identify DLT. The recommended dose was 4.0 mg/m(2), with one of 15 patients having DLT (grade 4 thrombocytopenia). Clearance was independent of body surface area; thus, a flat dose of 7.0 mg was used during expansion. Myelosuppression, mostly grade 4 neutropenia, occurred in 40% of patients but was transient and manageable, and none was febrile. All other toxicity was mild and fatigue, nausea and vomiting were the most common at the recommended dose. Pharmacokinetic parameters showed high interindividual variation, though linearity was observed. At or above the recommended dose, the myelosuppressive effect was significantly associated with the area under the concentration-time curve from time zero to infinity (white blood cells, P = 0.0007; absolute neutrophil count, P = 0.016). A partial response was observed in one patient with pancreatic adenocarcinoma at the recommended dose. CONCLUSION: A flat dose of 7.0 mg is the recommended dose for PM01183 as a 1-hour infusion q3wk. This dose is tolerated and active. Severe neutropenia occurred at this dose, although it was transient and with no clinical consequences in this study.

Phase I study of carboplatin in combination with PM00104 (Zalypsis®) in patients with advanced solid tumors.

This phase I trial determined the recommended dose for phase II trials (RD) of carboplatin 1-h intravenous (i.v.) infusion followed by PM00104 1-h i.v. infusion on Day 1 every 3 weeks (q3wk) in adult patients with advanced solid tumors. A toxicity-guided, dose-escalation design was used. Patients were stratified and divided into heavily (n = 6) or mildly pretreated (n = 14) groups. Transient grade 4 thrombocytopenia (in one heavily and three mildly pretreated patients) was the only dose-limiting toxicity (DLT) observed. Carboplatin AUC3-PM00104 2.0 mg/m(2) was the RD in both groups. At this RD, the carboplatin AUC was equal to ~60 % the target AUC used in other combinations, and the PM00104 dose intensity was 56-67 % of the value achieved at the RD for single-agent PM00104 given as 1-h infusion q3wk. Most treatment-related adverse events were grade 1/2. They mainly consisted of gastrointestinal and general symptoms, such as fatigue, anorexia, mucosal inflammation or nausea. Transient neutropenia (50 % of patients) and thrombocytopenia (33-38 %) were the most common severe hematological abnormalities; their incidence was higher than with single-agent PM00104. No pharmacokinetic drug-drug alterations occurred. Partial response was found in one patient with triple negative breast cancer pretreated with paclitaxel/bevacizumab. Three patients with colorectal cancer, head and neck cancer, and tumor of unknown origin had disease stabilization for ≥3 months. In conclusion, no optimal dose was reached due to overlapping myelosuppression despite stratification according to prior treatment. Therefore, this carboplatin plus PM00104 combination was not selected for further clinical research.

Phase II clinical trial of PM00104 (Zalypsis(®)) in urothelial carcinoma patients progressing after first-line platinum-based regimen.

PURPOSE: This exploratory phase II clinical trial evaluated the antitumor activity, safety profile and pharmacokinetics of PM00104 (Zalypsis(®)) 3 mg/m(2) 1 h every 3-week intravenous infusion in patients with advanced and/or metastatic urothelial carcinoma progressing after first-line platinum-based chemotherapy. METHODS: The primary efficacy end point was the disease control rate (DCR), defined as the percentage of patients with confirmed objective response or progression-free at 3 months, according to the response evaluation criteria in solid tumors. RESULTS: In a first stage (n = 19 patients evaluable for efficacy), only one patient achieved DCR (stable disease as best response and progression-free survival of 3.1 months). According to the 2-stage design used, the primary efficacy objective was unmet, and therefore, the trial was finalized without opening the second stage. The most common adverse events related to PM00104 were fatigue, anorexia, nausea, troponin I increase and neutropenia, which were transient and manageable with dose modifications or administration delays. Mean PK results (Cmax = 48.57 µg/l and area under the curve (AUC) = 154.97 h µg/l) were similar to those observed in a previous phase I trial evaluating the same dose and schedule. Few troponin I concentrations were higher than 0.10 ng/ml, and none of them were related to parameters of PM00104 exposure such as AUC or Cmax. CONCLUSIONS: No recommendation is given for further evaluation of PM00104 as single-agent treatment of patients with pretreated advanced and/or metastatic urothelial carcinoma. No new safety signals were observed.

Phase I clinical and pharmacokinetic study of trabectedin and cisplatin given every three weeks in patients with advanced solid tumors.

The aim of this phase I study was to identify a feasible dose and schedule for the combination of cisplatin and trabectedin. The regimen evaluated consisted of cisplatin at a fixed dose of 75 mg/m(2) 1-hour intravenous (i.v.) infusion followed by escalating doses of trabectedin 3-hour i.v. infusion, both administered on day 1 every 3 weeks (q3wks). Two dose-limiting toxicities (DLTs), grade 4 neutropenia longer than 7 days duration and grade 3 vomiting despite standard antiemetic therapy, occurred at the starting dose of trabectedin (0.75 mg/m(2)). The immediately lower dose (trabectedin 0.60 mg/m(2)) was evaluated in a total of 8 patients; no DLTs occurred and this was declared the recommended dose (RD). The safety profile of the combination at this dose and schedule was consistent with the known side effects of each agent alone: nausea, fatigue, transient transaminase elevations and neutropenia. No new or unexpected adverse reactions were observed. Two partial responses were reported at the RD in patients with pretreated ovarian cancer. Comparison with population pharmacokinetic data suggests a PK interaction between trabectedin and cisplatin leading to increased plasma exposure of trabectedin in the first 48 h, lower platinum clearance and longer half-life. In conclusion, although the trabectedin dose achieved with this combination was low (50 % of single-agent when given q3wks), this day 1 q3wks trabectedin plus cisplatin combination showed a feasible administration, a tolerable safety profile and some antitumor activity.