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.
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.
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.
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.
G1 Therapeutics.
ERRB2 (formerly HER2)-positive advanced breast cancer (ABC) remains typically incurable with optimal treatment undefined in later lines of therapy. The chimeric antibody margetuximab shares ERBB2 ...specificity with trastuzumab but incorporates an engineered Fc region to increase immune activation.
To compare the clinical efficacy of margetuximab vs trastuzumab, each with chemotherapy, in patients with pretreated ERBB2-positive ABC.
The SOPHIA phase 3 randomized open-label trial of margetuximab plus chemotherapy vs trastuzumab plus chemotherapy enrolled 536 patients from August 26, 2015, to October 10, 2018, at 166 sites in 17 countries. Eligible patients had disease progression on 2 or more prior anti-ERBB2 therapies and 1 to 3 lines of therapy for metastatic disease. Data were analyzed from February 2019 to October 2019.
Investigators selected chemotherapy before 1:1 randomization to margetuximab, 15 mg/kg, or trastuzumab, 6 mg/kg (loading dose, 8 mg/kg), each in 3-week cycles. Stratification factors were metastatic sites (≤2, >2), lines of therapy (≤2, >2), and chemotherapy choice.
Sequential primary end points were progression-free survival (PFS) by central blinded analysis and overall survival (OS). All α was allocated to PFS, followed by OS. Secondary end points were investigator-assessed PFS and objective response rate by central blinded analysis.
A total of 536 patients were randomized to receive margetuximab (n = 266) or trastuzumab (n = 270). The median age was 56 (27-86) years; 266 (100%) women were in the margetuximab group, while 267 (98.9%) women were in the trastuzumab group. Groups were balanced. All but 1 patient had received prior pertuzumab, and 489 (91.2%) had received prior ado-trastuzumab emtansine. Margetuximab improved primary PFS over trastuzumab with 24% relative risk reduction (hazard ratio HR, 0.76; 95% CI, 0.59-0.98; P = .03; median, 5.8 95% CI, 5.5-7.0 months vs 4.9 95% CI, 4.2-5.6 months; October 10, 2018). After the second planned interim analysis of 270 deaths, median OS was 21.6 months with margetuximab vs 19.8 months with trastuzumab (HR, 0.89; 95% CI, 0.69-1.13; P = .33; September 10, 2019), and investigator-assessed PFS showed 29% relative risk reduction favoring margetuximab (HR, 0.71; 95% CI, 0.58-0.86; P < .001; median, 5.7 vs 4.4 months; September 10, 2019). Margetuximab improved objective response rate over trastuzumab: 22% vs 16% (P = .06; October 10, 2018), and 25% vs 14% (P < .001; September 10, 2019). Incidence of infusion-related reactions, mostly in cycle 1, was higher with margetuximab (35 13.3% vs 9 3.4%); otherwise, safety was comparable.
In this phase 3 randomized clinical trial, margetuximab plus chemotherapy had acceptable safety and a statistically significant improvement in PFS compared with trastuzumab plus chemotherapy in ERBB2-positive ABC after progression on 2 or more prior anti-ERBB2 therapies. Final OS analysis is expected in 2021.
ClinicalTrials.gov Identifier: NCT02492711.
To assess safety and efficacy of niraparib + bevacizumab as a first-line maintenance therapy for patients with newly diagnosed advanced ovarian cancer.
This multicenter, phase II, single-arm, ...open-label study enrolled adult patients with stage IIIB to IV ovarian, fallopian tube, or primary peritoneal cancer (NCT03326193). Patients were required to have an attempt at debulking surgery and have a complete response, partial response, or no evidence of disease following first-line, platinum-based chemotherapy with ≥3 cycles of bevacizumab. The primary endpoint was the progression-free survival (PFS) rate at 18 months. Secondary endpoints included PFS, overall survival, and safety.
Among the 105 evaluable patients, the PFS rate at 18 months was 62% (95% CI 52–71%) in the overall population and 76% (95% CI 61–87) in the homologous recombination deficient (HRd), 47% (95% CI 31–64%) in the HR proficient (HRp), and 56% (95% CI 31–79%) in the HR not determined (HRnd) subgroups (December 24, 2020, cutoff). After a median follow-up time of 28.7 months (IQR, 23.9–32.5 months), median PFS was 19.6 months (95% CI 16.5–25.1) in the overall population (N = 105) and 28.3 months (95% CI 19.9–NE), 14.2 months (95% CI 8.6–16.8), and 12.1 months (95% CI 8.0–NE) in the HRd, HRp, and HRnd subgroups, respectively (June 16, 2021, cutoff). The most common any-grade treatment-related adverse events (related to niraparib and/or bevacizumab) were thrombocytopenia (74/105), fatigue (60/105), and anemia (55/105; December 24, 2020, cutoff).
Niraparib + bevacizumab first-line maintenance therapy displayed promising PFS results. Safety was consistent with the known safety profiles of niraparib and bevacizumab as monotherapy.
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•OVARIO enrolled patients with primary advanced-stage ovarian cancer, including high-risk cases.•In the overall population, 62% of patients were progression-free at the 18-month primary endpoint.•After a median follow-up of 28.7 months, median PFS was 19.6 months (overall), 28.3 months (HRd), and 14.2 months (HRp).•The most common any-grade adverse events related to niraparib and/or bevacizumab were thrombocytopenia, fatigue, and anemia.
JCO
Final overall survival (OS) in SOPHIA (ClinicalTrials.gov identifier: NCT02492711), a study of margetuximab versus trastuzumab, both with chemotherapy, in patients with previously treated human ...epidermal growth factor receptor 2-positive advanced breast cancer, is reported with updated safety. Overall, 536 patients in the intention-to-treat population were randomly assigned to margetuximab (15 mg/kg intravenously once every 3 weeks; n = 266) plus chemotherapy or trastuzumab (6 mg/kg intravenously once every 3 weeks after a loading dose of 8 mg/kg; n = 270) plus chemotherapy. Primary end points were progression-free survival, previously reported, and OS. Final OS analysis was triggered by 385 prespecified events. The median OS was 21.6 months (95% CI, 18.89 to 25.07) with margetuximab versus 21.9 months (95% CI, 18.69 to 24.18) with trastuzumab (hazard ratio HR, 0.95; 95% CI, 0.77 to 1.17;
= .620). Preplanned, exploratory analysis of CD16A genotyping suggested a possible improvement in OS for margetuximab in CD16A-158FF patients versus trastuzumab (median OS, 23.6
19.2 months; HR, 0.72; 95% CI, 0.52 to 1.00) and a possible improvement in OS for trastuzumab in CD16A-158VV patients versus margetuximab (median OS, 31.1
22.0 months; HR, 1.77; 95% CI, 1.01 to 3.12). Margetuximab safety was comparable with trastuzumab. Final overall OS analysis did not demonstrate margetuximab advantage over trastuzumab. Margetuximab studies in patients with human epidermal growth factor receptor 2-positive breast cancer with different CD16A allelic variants are warranted.
We report final antitumor efficacy results from a phase II study of trilaciclib, an intravenous cyclin-dependent kinase 4/6 (CDK4/6) inhibitor, administered prior to gemcitabine plus carboplatin ...(GCb) in patients with metastatic triple-negative breast cancer (NCT02978716).
Patients were randomized (1:1:1) to group 1 GCb (days 1, 8); n = 34, group 2 trilaciclib prior to GCb (days 1, 8); n = 33, or group 3 trilaciclib (days 1, 8) and trilaciclib prior to GCb (days 2, 9); n = 35. Subgroup analyses were performed according to CDK4/6 dependence, level of programmed death-ligand 1 (PD-L1) expression, and RNA-based immune signatures using proportional hazards regression. T-cell receptor (TCR) β CDR3 regions were amplified and sequenced to identify, quantify, and compare the abundance of each unique TCRβ CDR3 at baseline and on treatment.
Median overall survival (OS) was 12.6 months in group 1, not reached in group 2 (HR = 0.31; P = 0.0016), 17.8 months in group 3 (HR = 0.40; P = 0.0004), and 19.8 months in groups 2 and 3 combined (HR = 0.37; P < 0.0001). Efficacy outcomes were comparable regardless of cancer CDK4/6 dependence status and immune signatures. Administering trilaciclib prior to GCb prolonged OS irrespective of PD-L1 status but had greater benefit in the PD-L1-positive population. T-cell activation was enhanced in patients receiving trilaciclib.
Administering trilaciclib prior to GCb enhanced antitumor efficacy, with significant improvements in OS. Efficacy outcomes in immunologic subgroups and enhancements in T-cell activation suggest these improvements may be mediated via immunologic mechanisms.
Purpose
Androgen receptor (AR) expression occurs in up to 86% of human epidermal growth factor receptor 2-positive (HER2+) breast cancers. In vitro
,
AR inhibitors enhance antitumor activity of ...trastuzumab, an anti-HER2 antibody, in trastuzumab-resistant HER2+ cell lines. This open-label, single-arm, phase II study evaluated the efficacy and safety of enzalutamide, an AR-signaling inhibitor, in patients with advanced HER2+ AR+ breast cancer previously treated with trastuzumab.
Methods
Eligible patients had measurable or non-measurable evaluable disease per Response Evaluation Criteria in Solid Tumors (RECIST) v1.1, Eastern Cooperative Oncology Group status ≤ 1, no history of brain metastases, and previously received ≥ 1 anti-HER2 regimen for advanced disease. Patients received 160 mg oral enzalutamide daily and 6 mg/kg intravenous trastuzumab every 21 days until disease progression or unacceptable toxicity. Primary end point was clinical benefit rate at 24 weeks (CBR24); secondary end points included progression-free survival (PFS) and safety.
Results
Overall, 103 women were enrolled median age 60 years (range 34–83); 62% had received ≥ 3 lines of prior anti-HER2 therapy. CBR24, comprising patients with confirmed partial responses (5%) and durable stable disease at 24 weeks (19%), was 24% in the efficacy evaluable set (
n
= 89). CBR24 did not seem related to AR-expression levels or hormone receptor status. Median PFS was 3.4 months (95% confidence interval 2.0–3.8). Overall, 97 (94%) patients experienced treatment-emergent adverse events (TEAEs), with fatigue most common (34%). Dyspnea (4%) and malignant neoplasm progression (3%) were the only TEAEs grade ≥ 3 reported in ≥ 3 patients. 22 patients (21%) reported serious TEAEs. Four patients (4%) experienced fatal, non-drug-related TEAEs.
Conclusions
Enzalutamide plus trastuzumab was well tolerated, and a subset of patients in this heavily pretreated population had durable disease control. Determination of biomarkers is needed to identify patients most likely to benefit from this combination.
ClinicalTrials.gov number
NCT02091960
The METRIC study (NCT#0199733) explored a novel antibody-drug conjugate, glembatumumab vedotin (GV), targeting gpNMB that is overexpressed in ~40% of patients with triple-negative breast cancer ...(TNBC) and associated with poor prognosis. The study was a randomized, open-label, phase 2b study that evaluated progression-free survival (PFS) of GV compared with capecitabine in gpNMB-overexpressing TNBC. Patients who had previously received anthracycline and taxane-based therapy were randomized 2:1 to receive, GV (1.88 mg/kg IV q21 days) or capecitabine (2500 mg/m
PO daily d1-14 q21 days). The primary endpoint was RECIST 1.1 PFS per independent, blinded central review. In all, 327 patients were randomized to GV (213 treated) or capecitabine (92 treated). Median PFS was 2.9 months for GV vs. 2.8 months for capecitabine. The most common grade ≥3 toxicities for GV were neutropenia, rash, and leukopenia, and for capecitabine were fatigue, diarrhea, and palmar-plantar erythrodysesthesia. The study did not meet the primary endpoint of improved PFS over capecitabine or demonstrate a relative risk/benefit improvement over capecitabine.
Objective
Our objective was to evaluate the factors associated with regional variation of rheumatoid arthritis (RA) disease burden in the US.
Methods
In a retrospective cohort analysis of ...Rheumatology Informatics System for Effectiveness (RISE) registry data, seropositivity, RA disease activity (Clinical Disease Activity Index CDAI, Routine Assessment of Patient Index Data–version 3 RAPID3), socioeconomic status (SES), geographic region, health insurance type, and comorbidity burden were recorded. An Area Deprivation Index score of more than 80 defined low SES. Median travel distance to practice sites’ zip codes was calculated. Linear regression was used to analyze associations between RA disease activity and comorbidity adjusting for age, sex, geographic region, race, and insurance type.
Results
Enrollment data for 184,722 patients with RA from 182 RISE sites were analyzed. Disease activity was higher in African American patients, in those from Southern regions, and in those with Medicaid or Medicare coverage. Greater comorbidity was prevalent in patients in the South and those with Medicare or Medicaid coverage. There was moderate correlation between comorbidity and disease activity (Pearson coefficient: RAPID3 0.28, CDAI 0.15). High‐deprivation areas were mainly in the South. Less than 10% of all participating practices cared for more than 50% of all Medicaid recipients. Patients living more than 200 miles away from specialist care were located mainly in Southern and Western regions.
Conclusion
A disproportionately large portion of socially deprived, high comorbidity, and Medicaid‐covered patients with RA were cared for by a minority of rheumatology practices. Studies are needed in high‐deprivation areas to establish more equitable distribution of specialty care for patients with RA.
Objective
To evaluate the regional variation of cost sharing and associations with rheumatoid arthritis (RA) disease burden in the US.
Methods
Patients with RA from rheumatology practices in ...Northeast, South, and West US regions were evaluated. Sociodemographics, RA disease status, and comorbidities were collected, and Rheumatic Disease Comorbidity Index (RDCI) score was calculated. Primary insurance types and copay for office visits (OVs) and medications were documented. Univariable pairwise differences between regions were conducted, and multivariable regression models were estimated to evaluate associations of RDCI with insurance, geographical region, and race.
Results
In a cohort of 402 predominantly female, White patients with RA, most received government versus private sponsored primary insurance (40% vs. 27.9%). Disease activity and RDCI were highest for patients in the South region, where copays for OVs were more frequently more than $25. Copays for OVs and medications were less than $10 in 45% and 31.8% of observations, respectively, and more prevalent in the Northeast and West patient subsets than in the South subset. Overall, RDCI score was significantly higher for OV copays less than $10 as well as for medication copays less than $25, both independent of region or race. Additionally, RDCI was significantly lower for privately insured than Medicare individuals (RDCI −0.78, 95% CI −0.41 to −1.15, P < 0.001) and Medicaid (RDCI −0.83, 95% CI −0.13 to −1.54, P = 0.020), independent of region and race.
Conclusion
Cost sharing may not facilitate optimum care for patients with RA, especially in the Southern regions. More support may be required of government insurance plans to accommodate patients with RA with a high disease burden.