Vascular endothelial growth factor-targeted therapy in patients with renal cell carcinoma pretreated with immune checkpoint inhibitors: A systematic literature review

INTRODUCTION

We conducted a systematic literature review to identify evidence for use of vascular endothelial growth factor (VEGF)-targeted (anti-VEGF) treatment in patients with renal cell carcinoma (RCC) following prior checkpoint inhibitor (CPI)-based therapy.

METHODS

This was a PRISMA-standard systematic literature review; registered with PROSPERO (CRD42021255568). Literature searches were conducted in MEDLINE®, Embase, and the Cochrane Library (January 28, 2021; updated September 13, 2022) to identify publications reporting efficacy/effectiveness and safety/tolerability evidence for anti-VEGF treatment in patients with RCC who had received prior CPI therapy.

RESULTS

Of 2,639 publications screened, 48 were eligible and featured 2,759 patients treated in trials and 2,209 in real-world studies (RWS). Most patients with available data were treated with anti-VEGF tyrosine kinase inhibitor-based regimens (trials: 93 %; RWS: 100 %), most commonly cabozantinib, which accounted for 46 % of trial and 62 % of RWS patients in publications with available data. Collectively, there was consistent evidence of anti-VEGF treatment activity after prior CPI therapy. Activity was reported for all anti-VEGF regimens and regardless of prior CPI-based regimen. No new safety signals were detected for subsequent anti-VEGF therapy; no studies suggested increased immune-related adverse events associated with prior CPI therapy. The results were limited by data quality; study heterogeneity prohibited meta-analyses.

CONCLUSION

Based on the available data (most commonly for cabozantinib), anti-VEGF therapy appears to be a rational treatment choice in patients with RCC who have progressed despite prior CPI-based therapy. Results from ongoing trials of combination anti-VEGF plus CPI regimen post prior CPI therapy trials will contribute more definitive evidence.

PLAIN LANGUAGE SUMMARY

Anticancer treatments that work by reducing levels of a substance in the body called Vascular Endothelial Growth Factor are known as anti-VEGF drugs. Reducing VEGF levels helps to reduce blood supply to tumors, which can slow the speed at which the cancer grows. Some other types of anticancer drugs that help the immune system to fight cancer cells are called checkpoint inhibitors. Here, we looked at published studies that investigated how anti-VEGF drugs work, and what side effects they cause, in people who have already been treated with checkpoint inhibitors for a type of kidney cancer called renal cell carcinoma. We aimed to summarize the available evidence to help doctors decide how best to use anti-VEGF drugs in these patients. We found 48 studies that included almost 5,000 patients. The results of the studies showed that anti-VEGF drugs have anticancer effects in people with renal cell carcinoma who had already been treated with checkpoint inhibitors. All of the VEGF-targeting drugs had anticancer effects, irrespective of what checkpoint inhibitor treatment people had received before. There were different amounts of evidence available for the different anti-VEGF drugs. The anti-VEGF cabozantinib had the largest amount of evidence. Importantly, previous checkpoint inhibitor treatment did not seem to affect the number or type of side-effects associated with anti-VEGF drugs. Results from ongoing, well-designed studies will be helpful to confirm these results. Our findings may be useful for doctors considering using anti-VEGF drugs in patients with renal cell carcinoma who have received checkpoint inhibitor treatment.

Cabozantinib after prior checkpoint inhibitor therapy in patients with solid tumors: A systematic literature review

INTRODUCTION

We conducted a systematic literature review to identify evidence for cabozantinib activity in patients with solid tumors after prior checkpoint inhibitor (CPI) therapy.

METHODS

The review was conducted according to PRISMA guidelines and registered with PROSPERO (CRD42021259873). MEDLINE®, Embase, and the Cochrane Library were searched on 19 May 2021 to identify publications reporting the efficacy/effectiveness and safety/tolerability of cabozantinib in patients with solid tumors who had received prior CPI-based therapy. Publications were screened by one reviewer with uncertainties resolved by a second and/or the full author group. Risk of bias was assessed using Gradingof Recommendations Assessment, Development and Evaluation (GRADE) for clinical trials and the Newcastle-Ottawa Scale (NOS) for observational studies.

RESULTS

Of 669 publications screened, 21 were eligible: 18 reported data on renal cell carcinoma, and one each for hepatocellular carcinoma, metastatic urothelial carcinoma, and non-small cell lung cancer. Of six trial publications, three reported moderate-quality evidence and three low-quality evidence. Of 15 observational studies, NOS scores ranged from 3 to 6, suggesting a high potential for uncertainty. The studies consistently reported clinical activity for cabozantinib after CPI therapy, across treatment lines and tumor types, with no new safety signals. The findings were limited by the quality and quantity of available data.

CONCLUSION

Cabozantinib appears to have anti-tumor activity after prior CPI therapy in patients with solid tumors. Our results are driven largely by studies in renal cell carcinoma. Evidence from ongoing phase 3 trials is required to establish further the role of cabozantinib after CPI therapy.

Current and emerging therapies for first-line treatment of metastatic clear cell renal cell carcinoma

There has been significant progress in the treatment of patients with advanced clear cell renal cell carcinoma (ccRCC), with improved knowledge of disease biology and the introduction of targeted agents and immunotherapies. In this review, we discuss current and emerging first-line treatment options, including recent approvals of the tyrosine kinase inhibitor (TKI) cabozantinib and the immunotherapy combination of nivolumab (anti-programmed cell death 1 [PD-1])/ipilimumab (anti-cytotoxic T-lymphocyte-associated antigen 4 [CTLA-4]), and initial outcomes with the combination of atezolizumab (anti-PD-ligand 1 [PD-L1])/bevacizumab (anti-vascular endothelial growth factor [VEGF]). Key clinical data are reviewed, as these novel first-line treatments offer significant improvement, particularly for patients classified as intermediate/poor risk for whom previously available therapies have demonstrated limited efficacy. Treatment recommendations based on clinical evidence and expert opinion are discussed. We also review ongoing studies investigating combinations of checkpoint inhibitors with TKIs, including cabozantinib and axitinib, and with other novel immunomodulatory agents, and the potential role of single-agent immunotherapy for select patients. With a growing treatment armamentarium, identification and validation of biomarkers will be crucial for optimizing first-line selection and treatment sequences.

Targeting the Tumor Microenvironment with Immunotherapy for Genitourinary Malignancies

OPINION STATEMENT

Bacillus Calmette-Guérin in urothelial carcinoma, high-dose interleukin-2 in renal cell carcinoma, and sipuleucel-T in prostate cancer serve as enduring examples that the host immune response can be harnessed to promote effective anti-tumor immunity in genitourinary malignancies. Recently, cancer immunotherapy with immune checkpoint inhibitors has transformed the prognostic landscape leading to durable responses in a subset of urothelial carcinoma and renal cell carcinoma patients with traditionally poor prognosis. Despite this success, many patients fail to respond to immune checkpoint inhibitors and progression/relapse remains common. Furthermore, modest clinical activity has been observed with ICIs as a monotherapy in advanced PCa. As such, novel treatment approaches are warranted and improved biomarkers for patient selection and treatment response are desperately needed. Future efforts should focus on exploring synergistic and rational combinations that safely and effectively boost response rates and survival in genitourinary malignancies. Specific areas of interest include (1) evaluating the optimal sequencing, disease burden, and timing of immuno-oncology agents with other anti-cancer therapeutics and (2) validating novel biomarkers of response to immunotherapy to optimize patient selection and to identify individuals most likely to benefit from immunotherapy across the heterogenous spectrum of genitourinary malignancies.