ENGOT-ov-6/TRINOVA-2: Randomised, double-blind, phase 3 study of pegylated liposomal doxorubicin plus trebananib or placebo in women with recurrent partially platinum-sensitive or resistant ovarian cancer

AIMS

Trebananib, a peptide-Fc fusion protein, inhibits angiogenesis by inhibiting binding of angiopoietin-1/2 to the receptor tyrosine kinase Tie2. This randomised, double-blind, placebo-controlled phase 3 study evaluated whether trebananib plus pegylated liposomal doxorubicin (PLD) improved progression-free survival (PFS) in patients with recurrent epithelial ovarian cancer.

METHODS

Women with recurrent ovarian cancer (platinum-free interval ≤12 months) were randomised to intravenous PLD 50 mg/m² once every 4 weeks plus weekly intravenous trebananib 15 mg/kg or placebo. PFS was the primary end-point; key secondary end-points were objective response rate (ORR) and duration of response (DOR). Owing to PLD shortages, enrolment was paused for 13 months; the study was subsequently truncated.

RESULTS

Two hundred twenty-three patients were enrolled. Median PFS was 7.6 months (95% CI, 7.2-9.0) in the trebananib arm and 7.2 months (95% CI, 4.8-8.2) in the placebo arm, with a hazard ratio of 0.92 (95% CI, 0.68-1.24). However, because the proportional hazards assumption was not fulfilled, the standard Cox model did not provide a reliable estimate of the hazard ratio. ORR in the trebananib arm was 46% versus 21% in the placebo arm (odds ratio, 3.43; 95% CI, 1.78-6.64). Median DOR was improved (trebananib, 7.4 months [95% CI, 5.7-7.6]; placebo, 3.9 months [95% CI, 2.3-6.5]). Adverse events with a greater incidence in the trebananib arm included localised oedema (61% versus 32%), ascites (29% versus 9%) and vomiting (45% versus 33%).

CONCLUSIONS

Trebananib demonstrated anticancer activity in this phase 3 study, indicated by improved ORR and DOR. Median PFS was not improved. No new safety signals were identified.

TRIAL REGISTRATION

ClinicalTrials.gov, NCT01281254.

Characterization of patients with long-term responses to rucaparib treatment in recurrent ovarian cancer

OBJECTIVE

To describe molecular and clinical characteristics of patients with high-grade recurrent ovarian carcinoma (HGOC) who had long-term responses to the poly(ADP-ribose) polymerase (PARP) inhibitor rucaparib.

METHODS

This post hoc analysis pooled patients from Study 10 (NCT01482715; Parts 2A and 2B; n = 54) and ARIEL2 (NCT01891344; Parts 1 and 2; n = 491). Patients with investigator-assessed complete or partial response per RECIST were classified based on duration of response (DOR): long (≥1 year), intermediate (6 months to <1 year), or short (<6 months). Next-generation sequencing was used to detect deleterious mutations and loss of heterozygosity (LOH) in tumors.

RESULTS

Overall, 25.3% (138/545) of enrolled patients were responders. Of these, 27.5% (38/138) had long-term responses; 28.3% (39/138) were intermediate- and 34.8% (48/138) were short-term responders. Most of the long-term responders harbored a BRCA1 or BRCA2 (BRCA) mutation (71.1%, 27/38), and BRCA structural variants were most frequent among long-term responders (14.8%; 4/27). Responders with HGOC harboring a BRCA structural variant (n = 5) had significantly longer DOR than patients with other mutation types (n = 81; median not reached vs 0.62 years; HR, 0.21; 95% CI, 0.10-0.43; unadjusted p = 0.014). Among responders with BRCA wild-type HGOC, most long- and intermediate-term responders had high genome-wide LOH: 81.8% (9/11) and 76.9% (10/13), respectively, including 7 with deleterious RAD51C, RAD51D, or CDK12 mutations.

CONCLUSION

Among patients who responded to rucaparib, a substantial proportion achieved responses lasting ≥1 year. These analyses demonstrate the relationship between DOR to PARP inhibitor treatment and molecular characteristics in HGOC, such as presence of reversion-resistant BRCA structural variants.

Response durability after cessation of immune checkpoint inhibitors in patients with metastatic Merkel cell carcinoma: a retrospective multicenter DeCOG study

BACKGROUND

Immune checkpoint inhibitors (ICI) have led to a prolongation of progression-free and overall survival in patients with metastatic Merkel cell carcinoma (MCC). However, immune-mediated adverse events due to ICI therapy are common and often lead to treatment discontinuation. The response duration after cessation of ICI treatment is unknown. Hence, this study aimed to investigate the time to relapse after discontinuation of ICI in MCC patients.

METHODS

We analyzed 20 patients with metastatic MCC who have been retrospectively enrolled at eleven skin cancer centers in Germany. These patients have received ICI therapy and showed as best overall response (BOR) at least a stable disease (SD) upon ICI therapy. All patients have discontinued ICI therapy for other reasons than disease progression. Data on treatment duration, tumor response, treatment cessation, response durability, and tumor relapse were recorded.

RESULTS

Overall, 12 of 20 patients (60%) with MCC relapsed after discontinuation of ICI. The median response durability was 10.0 months. Complete response (CR) as BOR to ICI-treatment was observed in six patients, partial response (PR) in eleven, and SD in three patients. Disease progression was less frequent in patients with CR (2/6 patients relapsed) as compared to patients with PR (7/11) and SD (3/3), albeit the effect of initial BOR on the response durability was below statistical significance. The median duration of ICI therapy was 10.0 months. Our results did not show a correlation between treatment duration and the risk of relapse after treatment withdrawal. Major reasons for discontinuation of ICI therapy were CR (20%), adverse events (35%), fatigue (20%), or patient decision (25%). Discontinuation of ICI due to adverse events resulted in progressive disease (PD) in 71% of patients regardless of the initial response. A re-induction of ICI was initiated in 8 patients upon tumor progression. We observed a renewed tumor response in 4 of these 8 patients. Notably, all 4 patients showed an initial BOR of at least PR.

CONCLUSION

Our results from this contemporary cohort of patients with metastatic MCC indicate that MCC patients are at higher risk of relapse after discontinuation of ICI as compared to melanoma patients. Notably, the risk of disease progression after discontinuation of ICI treatment is lower in patients with initial CR (33%) as compared to patients with initial PR (66%) or SD (100%). Upon tumor progression, re-induction of ICI is a feasible option. Our data suggest that the BOR to initial ICI therapy might be a potential predictive clinical marker for a successful re-induction.

Independent action models and prediction of combination treatment effects for response rate, duration of response and tumor size change in oncology drug development

An unprecedented number of new cancer targets are in development, and most are being developed in combination therapies. Early oncology development is strategically challenged in choosing the best combinations to move forward to late stage development. The most common early endpoints to be assessed in such decision-making include objective response rate, duration of response and tumor size change. In this paper, using independent-drug-action and Bliss-drug-independence concepts as a foundation, we introduce simple models to predict combination therapy efficacy for duration of response and tumor size change. These models complement previous publications using the independent action models (Palmer 2017, Schmidt 2020) to predict progression-free survival and objective response rate and serve as new predictive models to understand drug combinations for early endpoints. The models can be applied to predict the combination treatment effect for early endpoints given monotherapy data, or to estimate the possible effect of one monotherapy in the combination if data are available from the combination therapy and the other monotherapy. Such quantitative work facilitates strategic planning and decision making in early stage oncology drug development.

Atezolizumab in locally advanced or metastatic urothelial cancer: a pooled analysis from the Spanish patients of the IMvigor 210 cohort 2 and 211 studies

Background

The studies IMvigor 210 cohort 2 and IMvigor211 evaluated the efficacy of atezolizumab in patients with locally advanced or metastatic urothelial cancer (mUC) upon progression to platinum-based chemotherapy worldwide. Yet, the real impact of this drug in specific geographical regions is unknown.

Materials and methods

We combined individual-level data from the 131 patients recruited in Spain from IMvigor210 cohort 2 and IMvigor211 in a pooled analysis. Efficacy and safety outcomes were assessed in the overall study population and according to PD-L1 expression on tumour-infiltrating immune cells.

Results

Full data were available for 127 patients; 74 (58%) received atezolizumab and 53 (42%) chemotherapy. Atezolizumab patients had a numerically superior median overall survival although not reaching statistical significance (9.2 months vs 7.7 months). No statistically significant differences between arms were observed in overall response rates (20.3% vs 37.0%) or progression-free survival (2.1 months vs 5.3 months). Nonetheless, median duration of response was superior for the immunotherapy arm (non-reached vs 6.4 months; p = 0.005). Additionally, among the responders, the 12-month survival rates seemed to favour atezolizumab (66.7% vs 19.9%). When efficacy was analyzed based on PD-L1 expression status, no significant differences were found. Treatment-related adverse events of any grade occurred more frequently in the chemotherapy arm [46/57 (81%) vs 44/74 (59%)].

Conclusion

Patients who achieved an objective response on atezolizumab presented a longer median duration of response and numerically superior 12 month survival rates when compared with chemotherapy responders along with a more favorable safety profile. PD-L1 expression did not discriminate patients who might benefit from atezolizumab.

Impact of cemiplimab treatment duration on clinical outcomes in advanced cutaneous squamous cell carcinoma

Treatment duration with checkpoint inhibitors must be optimized to prevent unjustified toxicity, but evidence for the management of cutaneous squamous cell carcinoma is lacking. A retrospective study was performed to evaluate the survival of patients with cutaneous squamous cell carcinoma (CSCC) who discontinued cemiplimab due to different causes and without progression. Among 95 patients with CSCC who received cemiplimab, 22 (23%) patients discontinued immunotherapy due to causes other than progression, such as comorbidities, toxicity, complete response or lack of compliance (group that discontinued before censoring [DBC]), then 73 patients had standard treatment scheduled (STS). The overall survival was 25.2 months (95% CI: 8.9-29.4) in STS group and 28.3 months (95% CI: 12.7-28.3) in the DBC group; deaths for all causes were 11/22 (50%) in the DBC group and 34/73 (46.6%) in the STS group (p = 0.32). 10/22 (45.4%) subjects died due to CSCC in the DBC after discontinuation and 34/73 (46.6%) in the STS group, and the difference between groups was not significant (p = 0.230). Duration of treatment was significantly lower in subjects with stable disease versus those with complete or partial response (16.9, 30.6 and 34.9 months, respectively; p = 0.004). Among the 22 STS patients, 12 received cemiplimab for less than 12 months (10 [83%] died) and 10 for at least 12 months (1 [10%] died). Our observation, finding no outcome difference between DBC and STS groups, suggests that ICI treatment after one year might expose patients to further treatment related events without efficacy advantages.

Assessment of added activity of an antitumor agent

An unprecedented number of novel oncology drugs are under preclinical and clinical development, and nearly all are developed in combinations. With an over-reliance on biological hypotheses, there is less effort to establish single agent activity before initiating late clinical development. This may be contributing to a decreased success rate going from phase 1 to approval in the immunotherapy era. Growing evidence in clinical trial data shows that the treatment benefit from most approved combination therapies can be explained by the independent drug action model. Using this working model, we develop a simple index to measure the added antitumor activity of a new drug based on mean response duration, an endpoint that naturally combines both response status and duration information for all patients, which is shown to be highly predictive of clinical benefit of FDA-approved anti-PD-(L)1 immunotherapies. This index sheds light on challenges and opportunities in contemporary oncology drug development and provides a practical tool to assist with decision-making in early clinical trials.

Inferences for the distribution of the duration of response in a comparative clinical study

Duration of response is an important endpoint used in drug development. Prolonged duration for response is often viewed as an early indication of treatment efficacy. However, there are numerous difficulties in studying the distribution of duration of response based on observed data subject to right censoring in practice. The most important obstacle is that the distribution of the duration of response is in general not identifiable in the presence of censoring due to the simple fact that there is no information on the joint distribution of time to response and time to progression beyond the largest follow-up time. In this article, we introduce the restricted duration of response as a replacement of the conventional duration of response. The distribution of restricted duration of response is estimable and we have proposed several nonparametric estimators in this article. The corresponding inference procedure and additional downstream analysis have been developed. Extensive numerical simulations have been conducted to examine the finite sample performance of the proposed estimators. It appears that a new regression-based two-step estimator for the survival function of the restricted duration of response tends to have a robust and superior performance, and we recommend its use in practice. A real data example from oncology has been used to illustrate the analysis for restricted duration of response.

Depth and Duration of Response Are Associated with Survival in Patients with Unresectable Hepatocellular Carcinoma: Exploratory Analyses of IMbrave150

Introduction

IMbrave150 established first-line atezolizumab plus bevacizumab as a global standard of care for unresectable hepatocellular carcinoma (HCC). We report exploratory analyses of associations between overall survival (OS) and depth of response (DpR) or duration of response (DoR).

Methods

IMbrave150 was a phase III randomized study of atezolizumab plus bevacizumab versus sorafenib in patients with unresectable HCC. DpR was defined as maximum tumor shrinkage from baseline based on the sum of longest diameters per independent review facility (IRF)-assessed RECIST 1.1. DoR was defined as time from first complete/partial response by IRF-assessed RECIST 1.1 until progression or death. Associations between OS and DpR or DoR were evaluated by scatterplot in both arms; OS and PFS were evaluated by DpR in atezolizumab plus bevacizumab-treated patients. To minimize immortal time bias, the DpR analysis included patients who survived ≥6 months.

Results

Of 312 and 140 patients with baseline measurable disease in the atezolizumab plus bevacizumab and sorafenib arms, respectively, 264 and 99 surviving ≥6 months were included in the DpR analysis, and 97 and 18 in the DoR analysis. Tumor shrinkage occurred in 230/312 (74%) patients in the atezolizumab plus bevacizumab arm and 76/140 (54%) in the sorafenib arm; their mean (SD) DpR was -42.5% (32.4%) and -25.0% (21.9%), respectively. Atezolizumab plus bevacizumab-treated ≥6-month survivors with DpR <0% had improved OS versus those with DpR ≥0% (HR: 0.29; 95% CI: 0.19-0.44). Those with deeper responses (DpR -100% to -60%) had longer OS than those with DpR ≥20% (unstratified HR: 0.08; 95% CI: 0.03-0.21). In scatterplots, DpR and DoR were generally associated with OS in both arms; interpretation was limited by censored patients.

Conclusions

DpR and DoR to atezolizumab plus bevacizumab and sorafenib were associated with OS in patients with unresectable HCC. More longer, deeper responses occurred with atezolizumab plus bevacizumab.

Long-Term Efficacy of Erythropoiesis-Stimulating Agents in Patients with Low-Risk or Intermediate-1-Risk Myelodysplastic Syndrome: Multicenter Real-Life Data

Objective

This study was undertaken to evaluate the long-term clinical efficacy of epoetin alfa and darbepoetin alfa in patients with myelodysplastic syndrome (MDS) in a real-life setting.

Materials and Methods

A total of 204 patients with low-risk or intermediate-1-risk MDS who received epoetin alfa or darbepoetin alfa were included. Hemoglobin levels and transfusion needs were recorded before treatment and at 12 months, 24 months, 36 months, and 48 months of treatment.

Results

At the 36-month (p=0.025) and 48-month (p=0.022) visits, epoetin alfa yielded significantly higher hemoglobin levels compared to darbepoetin alfa. Transfusion needs were also significantly lower with epoetin alfa compared to darbepoetin alfa at 24 months (p=0.012) and in the low-risk group compared to the intermediate-risk group at 24 months (p=0.018), 36 months (p=0.025), and 48 months (p<0.001). Treatment response rates at the 24-month, 36-month, and 48-month visits in the epoetin alfa (43.0%, 33.6%, and 27.1%), darbepoetin alfa (29.9%, 22.7%, and 16.5%), low-risk (39.3%, 30.0%, and 26.0%), and intermediate-risk (29.6%, 24.1%, and 11.1%) groups were lower than those obtained at 12 months, and the values differed significantly for the 36-month and 48-month visits with values ranging from p<0.05 to p<0.001.

Conclusion

This real-life long-term ESA extension study investigated the clinical efficacy of epoetin alfa and darbepoetin alfa for up to 48 months, revealing that treatment efficacy reached a plateau starting from the 24th month of therapy with a continuing decrease in treatment response rates regardless of treatment type, risk status, or gender. Nonetheless, significantly higher hemoglobin levels and marked improvement in transfusion needs were evident in epoetin-treated patients compared to darbepoetin-treated patients and in the low-risk group compared to the intermediate-risk group.

Effectiveness and safety of Atezolizumab in patients with locally-advanced or metastatic non-small cell lung cancer after prior chemotherapy under real-life conditions in Germany: The Non-interventional Study HYPERION

BACKGROUND

Atezolizumab is the first approved PD-L1 inhibitor for patients with advanced non-small cell lung cancer (NSCLC) in Germany. This study aimed to assess effectiveness and safety of this checkpoint inhibitor in clinical routine practice. In addition, potential correlating factors between patient or disease characteristics and clinical benefit of atezolizumab were addressed.

METHODS

HYPERION was a prospective, multicenter, non-interventional, two-cohort study collecting primary data in patients with locally-advanced or metastatic NSCLC after prior chemotherapy treated with atezolizumab. Patients were assigned to one of two cohorts depending on their clinical benefit from atezolizumab, i.e., lack of benefit (Cohort 1) or durability of clinical benefit and tumor response (Cohort 2), as assessed by the physicians.

RESULTS

Between May 2018 and August 2023, 353 patients were observed, including 179 in Cohort 1 and 174 in Cohort 2. The median age was 68 years and 61 % were men. The median time to loss of clinical benefit was 106 days (95 % CI: 93, 119) overall (n = 353 patients) and 256 days (95 % CI: 210, 339) for Cohort 2 (n = 174 patients). In total, 243 (68.8 %) patients experienced at least one adverse event (AE) and 146 (41.4 %) patients at least one serious AE. A higher proportion of PD-L1 positive patients was observed for Cohort 2 than for Cohort 1.

CONCLUSION

HYPERION confirmed effectiveness of atezolizumab in clinical practice. Results supported a known correlation between PD-L1 expression and a higher benefit of atezolizumab treatment. Atezolizumab treatment was associated with an acceptable safety profile.

MICRO ABSTRACT

The two-cohort non-interventional study HYPERION assessed the effectiveness and safety of atezolizumab in 353 patients with locally-advanced or metastatic NSCLC after prior chemotherapy, depending on lack of benefit (Cohort 1; n = 179) or durability of clinical benefit and tumor response (Cohort 2; n = 174). Atezolizumab showed effectiveness in clinical practice. Results were consistent with the known safety profile.