Myeloprotective Effects of Trilaciclib Among Patients with Small Cell Lung Cancer at Increased Risk of Chemotherapy-Induced Myelosuppression: Pooled Results from Three Phase 2, Randomized, Double-Blind, Placebo-Controlled Studies.

PURPOSE: Trilaciclib is an intravenous cyclin-dependent kinase 4/6 inhibitor indicated to decrease the incidence of chemotherapy-induced myelosuppression (CIM) by protecting hematopoietic stem and progenitor cells and immune system function from chemotherapy-induced damage (myeloprotection). Here, we investigated the myeloprotective effects of trilaciclib among patients at increased risk of CIM. PATIENTS AND METHODS: Data were pooled from three randomized, double-blind, placebo-controlled, phase 2 clinical studies of trilaciclib administered prior to chemotherapy in patients with extensive-stage small cell lung cancer (ES-SCLC). Myeloprotective outcomes were evaluated in patient subgroups based on age (<65 or ≥65 years), risk of chemotherapy-induced febrile neutropenia (FN), and risk of anemia or red blood cell (RBC) transfusions. For the FN and anemia analyses, risk factors were identified from published literature and used to classify patients into FN and anemia risk categories. Subgroup analysis based on age was also performed on patient reported outcome (PRO) measures. RESULTS: In total, 123 patients received trilaciclib and 119 patients received placebo. Myeloprotective benefits of trilaciclib were observed regardless of age, with greater effects observed among patients aged ≥65 years. Across FN risk factors and categories, trilaciclib had beneficial effects on neutrophil-related endpoints vs placebo, with greater effects observed in patients at higher risk of FN. Effects on RBC-related endpoints favored trilaciclib vs placebo, regardless of anemia risk factors and categories. Improvements in PROs with trilaciclib were observed irrespective of age group, but with greater improvements and less deterioration from baseline observed in older patients. CONCLUSION: By both decreasing the incidence of CIM and improving quality of life, trilaciclib has the potential to allow patients receiving chemotherapy for ES-SCLC, including patients who are older or more vulnerable to CIM, to receive chemotherapy on schedule and at standard-of-care doses, and to improve the experience for patients receiving chemotherapy to treat ES-SCLC. CLINICAL TRIAL NUMBERS: NCT02499770; NCT03041311; NCT02514447.

Effects of Trilaciclib on Chemotherapy-Induced Myelosuppression and Patient-Reported Outcomes in Patients with Extensive-Stage Small Cell Lung Cancer: Pooled Results from Three Phase II Randomized, Double-Blind, Placebo-Controlled Studies.

BACKGROUND: Chemotherapy-induced myelosuppression (CIM) and its sequalae cause significant side effects and harm to quality of life. Trilaciclib is an intravenous CDK4/6 inhibitor that is administered prior to chemotherapy to protect hematopoietic stem and progenitor cells from chemotherapy-induced damage (myeloprotection). PATIENTS AND METHODS: Data from three randomized, double-blind, placebo-controlled studies (NCT02499770, NCT03041311, and NCT02514447) were pooled to evaluate the effects of trilaciclib administered prior to standard-of-care chemotherapy (first-line etoposide plus carboplatin [E/P], first-line E/P plus atezolizumab, and second-/third-line topotecan) in patients with extensive-stage small cell lung cancer (ES-SCLC). The primary endpoints were duration of severe neutropenia (absolute neutrophil count < 0.5 × 109 cells/L) in cycle 1 and occurrence of severe neutropenia. Additional prespecified endpoints further assessed the effect of trilaciclib on myeloprotection, health-related quality of life (HRQoL), antitumor efficacy, and safety. RESULTS: Of 242 randomized patients, 123 received trilaciclib and 119 received placebo. Compared with placebo, administration of trilaciclib prior to chemotherapy resulted in significant decreases in most measures of multilineage CIM. The reduction in hematologic toxicity translated into the reduced need for supportive care interventions and hospitalizations due to CIM or sepsis and improvements in HRQoL domains related to the protected cell lineages, including fatigue, physical wellbeing, and functional wellbeing. Antitumor efficacy was similar for patients receiving trilaciclib or placebo. CONCLUSION: Administering trilaciclib prior to chemotherapy resulted in clinically meaningful reductions in CIM and its consequences and improved patient HRQoL, with no impact on the antitumor efficacy of three individual chemotherapy regimens used in the first- or second-/third-line treatment of ES-SCLC.

Myelopreservation with Trilaciclib in Patients Receiving Topotecan for Small Cell Lung Cancer: Results from a Randomized, Double-Blind, Placebo-Controlled Phase II Study.

INTRODUCTION: Multilineage myelosuppression is an acute toxicity of cytotoxic chemotherapy, resulting in serious complications and dose modifications. Current therapies are lineage specific and administered after chemotherapy damage has occurred. Trilaciclib is a cyclin-dependent kinase 4/6 inhibitor that is administered prior to chemotherapy to preserve hematopoietic stem and progenitor cells and immune system function during chemotherapy (myelopreservation). METHODS: In this randomized, double-blind, placebo-controlled phase II trial, patients with previously treated extensive-stage small cell lung cancer (ES-SCLC) were randomized to receive intravenous trilaciclib 240 mg/m2 or placebo before topotecan 1.5 mg/m2 on days 1-5 of each 21-day cycle. Primary endpoints were duration of severe neutropenia (DSN) in cycle 1 and occurrence of severe neutropenia (SN). Additional endpoints were prespecified to further assess the effect of trilaciclib on myelopreservation, safety, patient-reported outcomes (PROs), and antitumor efficacy. RESULTS: Thirty-two patients received trilaciclib, and 29 patients received placebo. Compared with placebo, administration of trilaciclib prior to topotecan resulted in statistically significant and clinically meaningful decreases in DSN in cycle 1 (mean [standard deviation] 2 [3.9] versus 7 [6.2] days; adjusted one-sided P < 0.0001) and occurrence of SN (40.6% versus 75.9%; adjusted one-sided P = 0.016), with numerical improvements in additional neutrophil, red blood cell, and platelet measures. Patients receiving trilaciclib had fewer grade ≥ 3 hematologic adverse events than patients receiving placebo, particularly neutropenia (75.0% versus 85.7%) and anemia (28.1% versus 60.7%). Myelopreservation benefits extended to improvements in PROs, specifically in those related to fatigue. Antitumor efficacy was comparable between treatment arms. CONCLUSIONS: Compared with placebo, the addition of trilaciclib prior to topotecan for the treatment of patients with previously treated ES-SCLC improves the patient experience of receiving chemotherapy, as demonstrated by a reduction in chemotherapy-induced myelosuppression, improved safety profile, improved quality of life and no detrimental effects on antitumor efficacy. TRIAL REGISTRATION: ClinicalTrials.gov: NCT02514447.

Trilaciclib prior to chemotherapy and atezolizumab in patients with newly diagnosed extensive-stage small cell lung cancer: A multicentre, randomised, double-blind, placebo-controlled Phase II trial.

Trilaciclib is an intravenous CDK4/6 inhibitor administered prior to chemotherapy to preserve haematopoietic stem and progenitor cells and immune system function from chemotherapy-induced damage (myelopreservation). The effects of administering trilaciclib prior to carboplatin, etoposide and atezolizumab (E/P/A) were evaluated in a randomised, double-blind, placebo-controlled Phase II study in patients with newly diagnosed extensive-stage small cell lung cancer (ES-SCLC) (NCT03041311). The primary endpoints were duration of severe neutropenia (SN; defined as absolute neutrophil count <0.5 × 109 cells per L) in Cycle 1 and occurrence of SN during the treatment period. Other endpoints were prespecified to assess the effects of trilaciclib on additional measures of myelopreservation, patient-reported outcomes, antitumour efficacy and safety. Fifty-two patients received trilaciclib prior to E/P/A and 53 patients received placebo. Compared to placebo, administration of trilaciclib resulted in statistically significant decreases in the mean duration of SN in Cycle 1 (0 vs 4 days; P < .0001) and occurrence of SN (1.9% vs 49.1%; P < .0001), with additional improvements in red blood cell and platelet measures and health-related quality of life (HRQoL). Trilaciclib was well tolerated, with fewer grade ≥3 adverse events compared with placebo, primarily due to less high-grade haematological toxicity. Antitumour efficacy outcomes were comparable. Administration of trilaciclib vs placebo generated more newly expanded peripheral T-cell clones (P = .019), with significantly greater expansion among patients with an antitumour response to E/P/A (P = .002). Compared with placebo, trilaciclib administered prior to E/P/A improved patients' experience of receiving treatment for ES-SCLC, as shown by reduced myelosuppression, and improved HRQoL and safety profiles.

Trilaciclib plus chemotherapy versus chemotherapy alone in patients with metastatic triple-negative breast cancer: a multicentre, randomised, open-label, phase 2 trial.

BACKGROUND: Trilaciclib is an intravenous cell-cycle inhibitor that transiently maintains immune cells and haemopoietic stem and progenitor cells in G1 arrest. By protecting the immune cells and bone marrow from chemotherapy-induced damage, trilaciclib has the potential to optimise antitumour activity while minimising myelotoxicity. We report safety and activity data for trilaciclib plus gemcitabine and carboplatin chemotherapy in patients with metastatic triple-negative breast cancer. METHODS: In this randomised, open-label, multicentre, phase 2 study, adult patients (aged ≥18 years) with evaluable, biopsy-confirmed, locally recurrent or metastatic triple-negative breast cancer who had no more than two previous lines of chemotherapy were recruited from 26 sites in the USA, three in Serbia, two in North Macedonia, one in Croatia, and one in Bulgaria; sites were academic and community hospitals. Availability of diagnostic samples of tumour tissue confirming triple-negative breast cancer was a prerequisite for enrolment. Eligible patients were randomly assigned (1:1:1) by an interactive web-response system, stratified by number of previous lines of systemic therapy and the presence of liver metastases, to receive intravenous gemcitabine 1000 mg/m2 and intravenous carboplatin (area under the concentration-time curve 2 µg × h/mL) on days 1 and 8 (group 1), gemcitabine and carboplatin plus intravenous trilaciclib 240 mg/m2 on days 1 and 8 (group 2), or gemcitabine and carboplatin on days 2 and 9 plus trilaciclib on days 1, 2, 8, and 9 (group 3) of 21-day cycles. Patients continued treatment until disease progression, unacceptable toxicity, withdrawal of consent, or discontinuation by the investigator. The primary objective was to assess the safety and tolerability of combining trilaciclib with gemcitabine and carboplatin chemotherapy. The primary endpoints were duration of severe neutropenia during cycle 1 and the occurrence of severe neutropenia during the treatment period. Overall survival was included as a key secondary endpoint. Analyses were in the intention-to-treat population. Safety was assessed in all patients who received at least one dose of study treatment. This study is registered with EudraCT, 2016-004466-26, and ClinicalTrials.gov, NCT02978716, and is ongoing but closed to accrual. FINDINGS: Between Feb 7, 2017, and May 15, 2018, 142 patients were assessed for eligibility and 102 were randomly assigned to group 1 (n=34), group 2 (n=33), or group 3 (n=35). Of all patients, 38 (37%) had received one or two lines of previous chemotherapy in the metastatic setting. Median follow-up was 8·4 months (IQR 3·8-13·6) for group 1, 12·7 months (5·5-17·4) for group 2, and 12·9 months (6·7-16·8) for group 3. Data cutoff for myelosuppression endpoints was July 30, 2018, and for antitumour activity endpoints was May 17, 2019. During cycle 1, mean duration of severe neutropenia was 0·8 day (SD 2·4) in group 1, 1·5 days (3·5) in group 2, and 1·0 day (2·6) in group 3 (group 3 vs group 1 one-sided adjusted p=0·70). Severe neutropenia occurred in nine (26%) of 34 patients in group 1, 12 (36%) of 33 patients in group 2, and eight (23%) of 35 patients in group 3 (p=0·70). Overall survival was 12·6 months (IQR 5·8-15·6) in group 1, 20·1 months (9·4-not reached) in group 2, and 17·8 months (8·8-not reached) in group 3 (group 3 vs group 1 two-sided p=0·0023). The most common treatment-emergent adverse events were anaemia (22 [73%] of 34), neutropenia (21 [70%]), and thrombocytopenia (18 [60%]) in group 1; neutropenia (27 [82%] of 33), thrombocytopenia (18 [55%]) and anaemia (17 [52%]) in group 2; and neutropenia (23 [66%] of 35), thrombocytopenia (22 [63%]), and nausea (17 [49%]) in group 3. There were no treatment-related deaths. INTERPRETATION: No significant differences were observed in myelosuppression endpoints with trilaciclib plus gemcitabine and carboplatin in patients with metastatic triple-negative breast cancer; however, the regimen was generally well tolerated and overall survival results were encouraging. Further studies of trilaciclib in this setting are warranted. FUNDING: G1 Therapeutics.

A phase I, open-label, two-stage study to investigate the safety, tolerability, pharmacokinetics, and pharmacodynamics of the oral AKT inhibitor GSK2141795 in patients with solid tumors.

Background We sought to determine the recommended phase II dose (RP2D) and schedule of GSK2141795, an oral pan-AKT kinase inhibitor. Patients and Methods Patients with solid tumors were enrolled in the dose-escalation phase. Pharmacokinetic (PK) analysis after a single dose (Cycle 0) informed dose escalation using accelerated dose titration. Once one grade 2 toxicity or dose-limiting toxicity was observed in Cycle 1, the accelerated dose titration was terminated and a 3 + 3 dose escalation was started. Continuous daily dosing was evaluated along with two intermittent regimens (7 days on/7 days off and 3 times per week). In the expansion phase at RP2D, patients with endometrial or prostate cancer, as well as those with select tumor types with a PIK3CA mutation, AKT mutation or PTEN loss, were enrolled. Patients were evaluated for adverse events (AEs), PK parameters, blood glucose and insulin levels, and tumor response. Results The RP2D of GSK2141795 for once-daily dosing is 75 mg. The most common (>10%) treatment-related AEs included diarrhea, fatigue, vomiting, and decreased appetite. Most AEs were low grade. The frequency of hyperglycemia increased with dose; however, at the RP2D, grade 3 hyperglycemia was only reported in 4% of patients and no grade 4 events were observed. PK characteristics were favorable, with a prolonged half-life and low peak-to-trough ratio. There were two partial responses at the RP2D in patients with either a PIK3CA mutation or PTEN loss. Conclusion GSK2141795 was safe and well-tolerated, with clinical activity seen as monotherapy at the RP2D of 75 mg daily. NCT00920257.

Effect of hepatic or renal impairment on the pharmacokinetics of casopitant, a NK-1 receptor antagonist.

Two studies were conducted in subjects with mild or moderate hepatic or renal impairment and subjects with normal organ function to evaluate the pharmacokinetics of casopitant and to assess its safety in these populations. A total of 26 subjects were enrolled in the hepatic impairment study and 18 subjects in the renal impairment study. All subjects received oral casopitant 100 mg once-daily for 5 days. Casopitant area under the concentration-time curve (AUC) increased 11% and 24% in subjects with mild or moderate hepatic impairment, respectively, on Day 1, compared with subjects with normal hepatic function; a similar increase was observed on Day 5. The AUC of the active major metabolite, GSK525060, was reduced 29% and 19% on Days 1 and 5, respectively, in subjects with moderate hepatic impairment, but not altered by mild hepatic impairment. Casopitant AUC increased 34% and 22% on Day 1 in subjects with mild or moderate renal impairment, respectively, and 28% and 11% on Day 5, respectively, compared with subjects with normal renal function. GSK525060 AUC was increased 17% and 24% on Days 1 and 5, respectively, in subjects with mild renal impairment; but did not significantly change in subjects with moderate renal impairment. Further age-adjusted analysis showed no meaningful effect of renal impairment on casopitant or GSK525060 AUC. Plasma protein binding of casopitant and GSK525060 was similar in all subjects. The pharmacokinetics of casopitant is not altered to a clinically significant extent in subjects with mild or moderate, hepatic or renal impairment. The impact of severe hepatic or renal impairment was not evaluated.