A Matching-adjusted Indirect Comparison of Nivolumab Plus Cabozantinib Versus Pembrolizumab Plus Axitinib in Patients with Advanced Renal Cell Carcinoma

BACKGROUND

The comparative efficacy and health-related quality of life (HRQoL) outcomes of nivolumab plus cabozantinib versus pembrolizumab plus axitinib as first-line treatments for advanced renal cell carcinoma (aRCC) have not been assessed in head-to-head trials.

OBJECTIVE

To assess the efficacy and HRQoL outcomes of nivolumab plus cabozantinib versus pembrolizumab plus axitinib.

DESIGN, SETTING, AND PARTICIPANTS

Patient-level data for nivolumab plus cabozantinib from the CheckMate 9ER trial and published data for pembrolizumab plus axitinib from the KEYNOTE-426 trial were used. CheckMate 9ER data were reweighted to match the key baseline characteristics as reported in KEYNOTE-426.

INTERVENTION

Nivolumab (240 mg every 2 wk) plus cabozantinib (40 mg once daily) and pembrolizumab (200 mg every 3 wk) plus axitinib (5 mg twice daily, initially).

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Hazard ratios (HRs) for progression-free survival (PFS), duration of response, overall survival (OS), and deterioration in HRQoL were assessed using weighted Cox proportional-hazard models, with sunitinib as a common anchor. Objective response rates (ORRs) and changes in HRQoL scores from baseline were assessed as difference-in-differences for the two treatments relative to sunitinib.

RESULTS AND LIMITATIONS

After balancing patient characteristics between the trials, nivolumab plus cabozantinib was associated with significantly improved PFS (HR [95% confidence interval {CI}] 0.70 [0.53-0.93]; p = 0.01) and a significantly decreased risk of confirmed deterioration in HRQoL (Functional Assessment of Cancer Therapy-Kidney Symptom Index-Disease-related Symptoms: HR [95% CI] 0.48 [0.34-0.69]) versus pembrolizumab plus axitinib. OS was similar between treatments (HR [95% CI] 0.99 [0.67-1.44]; p = 0.94). Nivolumab plus cabozantinib was associated with numerically greater ORRs (difference-in-difference [95% CI] 8.4% [-1.7 to 18.4]; p = 0.10) and longer duration of response (HR [95% CI] 0.79 [0.47-1.31]; p = 0.36) than pembrolizumab plus axitinib. Comparative studies using data with a longer duration of follow-up are warranted.

CONCLUSIONS

Nivolumab plus cabozantinib significantly improved PFS and HRQoL compared with pembrolizumab plus axitinib as first-line treatment for aRCC.

PATIENT SUMMARY

This study was conducted to indirectly compare the results of two immunotherapy-based combinations-nivolumab plus cabozantinib versus pembrolizumab plus axitinib-for patients who have not received any treatment for advanced renal cell carcinoma. Patients who received nivolumab plus cabozantinib had a significant improvement in the length of time without worsening of their disease and in their perceived physical and mental health compared with pembrolizumab plus axitinib; patients remained alive for a similar length of time from the start of either treatment. This analysis further adds to our current knowledge of the relative benefits of these two treatment regimens and will help with physician and patient treatment decisions.

Assessing treatment preferences among patients with advanced/metastatic renal cell carcinoma in the United States: A discrete choice experiment

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Background: The introduction of immunotherapies has changed the first-line treatment landscape for advanced/metastatic renal cell carcinoma (aRCC). This study examines patient preferences in this rapidly changing environment to better understand the tradeoffs patients with aRCC are willing to make when choosing treatment. Methods: Patients with self-reported aRCC in the United States completed an online, cross-sectional survey. A discrete choice experiment was used to assess preferences for attributes of aRCC treatments. Patients completed a series of choice tasks showing 2 treatment profiles that varied in 7 important attributes identified through literature and qualitative research: overall survival, progression-free survival (PFS), objective response rate (ORR), duration of response (DOR), risk of adverse events, quality of life (QOL) changes, and treatment administration. Descriptive statistics were reported, and a hierarchical Bayesian logistic model was used to calculate preference weights. Relative importance estimates (mean ± standard error) were computed for each attribute; these represent the mean percentage of the variation in preferences explained by the attribute. Results: Survey results from a total of 299 patients were analyzed (male, 50%; mean age, 56 years). All 7 attributes were statistically significant for influencing the choice of treatment. Key attributes included treatment regimen convenience and QOL improvement, which ranked similarly to increasing survival time. Among the efficacy attributes, increasing survival time was most important, followed by ORR, PFS, and DOR. Reducing the risk of serious adverse events from 82% to 65% was prioritized after the efficacy parameters. Conclusions: Patients with aRCC highly value less burdensome treatment regimens and improved QoL in addition to improvement in survival. This highlights the need for a broader context beyond efficacy and safety when discussing treatment options with patients. Funding: This study was supported by Bristol Myers Squibb.

Grade 3/4 Adverse Event Costs of Immuno-oncology Combination Therapies for Previously Untreated Advanced Renal Cell Carcinoma

BACKGROUND

Despite 4 approved combination regimens in the first-line setting for advanced renal cell carcinoma (aRCC), adverse event (AE) costs data are lacking.

MATERIALS AND METHODS

A descriptive analysis on 2 AE cost comparisons was conducted using patient-level data for the nivolumab-based therapies and published data for the pembrolizumab-based therapies. First, grade 3/4 AE costs were compared between nivolumab + ipilimumab vs. nivolumab + cabozantinib vs. pembrolizumab + axitinib using data from the CheckMate 214 (median follow-up [mFU]: 13.1 months), CheckMate 9ER (mFU: 12.8 months), and KEYNOTE-426 (mFU: 12.8 months) trials, respectively. Second, grade 3/4 AE costs were compared between nivolumab + ipilimumab vs. nivolumab + cabozantinib vs. pembrolizumab + lenvatinib using data from the CheckMate 214 (mFU: 26.7 months), CheckMate 9ER (mFU: 23.5 months), and KEYNOTE-581 (mFU: 26.6 months) trials, respectively. Per-patient costs for all-cause and treatment-related grade 3/4 AEs with corresponding any-grade AE rates ≥ 20% were calculated based on the Healthcare Cost and Utilization Project database and inflated to 2020 US dollars.

RESULTS

Per-patient all-cause grade 3/4 AE costs for nivolumab + ipilimumab vs. nivolumab + cabozantinib vs. pembrolizumab + axitinib were $2703 vs. $4508 vs. $5772, and treatment-related grade 3/4 AE costs were $741 vs. $2722 vs. $4440 over ~12.8 months of FU. For nivolumab + ipilimumab vs. nivolumab + cabozantinib vs. pembrolizumab + lenvatinib, per-patient all-cause grade 3/4 AE costs were $3120 vs. $5800 vs. $9285, while treatment-related grade 3/4 AE costs were $863 vs. $3162 vs. $5030 over ~26.6 months of FU.

CONCLUSION

Patients with aRCC treated with first-line nivolumab-based therapies had lower grade 3/4 all-cause and treatment-related AE costs than pembrolizumab-based therapies, suggesting a more favorable cost-benefit profile.

Temporal Trends in Grade 3/4 Adverse Events and Associated Costs of Nivolumab Plus Cabozantinib Versus Sunitinib for Previously Untreated Advanced Renal Cell Carcinoma

BACKGROUND AND OBJECTIVES

Novel immunotherapy-based combination treatments have drastically improved clinical outcomes for previously untreated patients with advanced/metastatic renal cell carcinoma (aRCC). This study aimed to assess the temporal trends in grade 3/4 adverse event (AE) rates and associated costs of nivolumab plus cabozantinib combination therapy versus sunitinib monotherapy in previously untreated patients with aRCC.

METHODS

Individual patient data from the CheckMate 9ER trial (nivolumab plus cabozantinib: N = 320; sunitinib: N = 320) were used to calculate the proportion of patients experiencing grade 3/4 AEs. AE unit costs were obtained from the United States (US) 2017 Healthcare Cost and Utilization Project (HCUP) and inflated to 2020 US dollars. Per-patient-per-month (PPPM) all-cause and treatment-related grade 3/4 AE costs over 18-months, temporal trends, and top drivers of AE costs were evaluated in both treatment arms.

RESULTS

Overall, the proportion of patients experiencing grade 3/4 AEs decreased over time, with the highest rates observed in the first 3 months for the nivolumab plus cabozantinib and sunitinib arms. Compared with sunitinib, nivolumab plus cabozantinib was associated with consistently lower average all-cause AE costs PPPM [month 3: $2021 vs. $3097 (p < 0.05); month 6: $1653 vs. $2418 (p < 0.05); month 12: $1450 vs. $1935 (p > 0.05); month 18: $1337 vs. $1755 (p > 0.05)]. Over 18 months, metabolism and nutrition disorders ($244), laboratory abnormalities ($182), and general disorders and administration site conditions ($122) were the costliest all-cause PPPM AE categories in the nivolumab plus cabozantinib arm, and laboratory abnormalities ($443), blood and lymphatic system disorders ($254), and metabolism and nutrition disorders ($177) were the costliest in the sunitinib arm. Trends of treatment-related AE costs were consistent with all-cause AE costs.

CONCLUSIONS

Nivolumab plus cabozantinib was associated with lower costs of grade 3/4 AE management PPPM than sunitinib, which accumulated over the 18-month study period.

Racial differences in treatment patterns and outcomes of first-line (1L) therapies for advanced renal cell carcinoma (aRCC) in the real-world (RW) setting

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Background: In 1L therapy for aRCC, nivolumab plus ipilimumab (NIVO+IPI) and pembrolizumab plus axitinib (PEM+AXI) have demonstrated significantly improved clinical outcomes versus sunitinib in phase III trials. African American/Black (AA) patients are grossly underrepresented in all aRCC trials. Little is known about the impact of racial differences on the use of 1L therapies and clinical outcomes in the RW setting. Methods: This retrospective chart review included AA and White American (WA) patients diagnosed with International Metastatic Renal Cell Carcinoma Database Consortium (IMDC)/Memorial Sloan Kettering Cancer Center (MSKCC) intermediate/poor (I/P)-risk aRCC who initiated on 1L NIVO+IPI, PEM+AXI, or tyrosine kinase inhibitor (TKI) monotherapy with sunitinib, pazopanib, or cabozantinib. Patients’ demographic/clinical characteristics and outcomes were abstracted from medical charts by treating oncologists. Use of 1L therapy, treatment discontinuation, and clinical outcomes including disease response, landmark progression-free survival (PFS), landmark overall survival (OS), and treatment-related adverse event (TRAE) rates were assessed descriptively by race. Results: Of 473 patients, 95 (20.1%) were AA, and 378 (79.9%) were WA patients. Median follow-up was 10.9 months. A higher proportion of AA vs. WA patients had received 1L TKI monotherapy (21.1% vs. 16.1%). Treatment discontinuation rate was higher in AA vs. WA patients (49.5% vs. 43.4%). Treatment response was lower in AA than WA patients (overall response rate [ORR]: 58.8% vs. 74.8%; complete response [CR]: 8.2% vs. 11.4%). The TRAE rate was slightly lower in AA vs. WA patients (25.3% vs. 32.5%). Stratified clinical outcomes including landmark PFS and OS rates at 6 and 9 months are shown in the Table. Conclusions: In this RW I/P-risk aRCC cohort, fewer AA patients were treated with standard of care immune-oncology (IO)-based therapy vs. WA patients, which may contribute to differences in therapy discontinuation and survival outcomes. Also, even with short follow-up, clinically meaningful ORR differences are noted in AA and WA patients. [Table: see text]

US physician perceptions of treatment decision making for advanced renal cell carcinoma

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Background: The immuno-oncology (IO) therapy combination nivolumab + ipilimumab, and the IO-tyrosine kinase inhibitor (TKI) combination pembrolizumab + axitinib, received US FDA approvals in 2018 and 2019, respectively, as first-line (1L) therapy for advanced renal cell carcinoma (aRCC). We examined physician perceptions of concerns about and barriers to 1L treatment by class of regimen (IO-IO, IO-TKI, and single-agent TKI [SA-TKI]) in the United States. Methods: US-based oncologists treating ≥ 5 aRCC patients in the prior 12 months were identified from the Cardinal Health network, a community of > 800 oncologists. Physicians were surveyed about concerns in prescribing and barriers to treating by class (scale of 1–5; 1 = no concern/not a barrier, 5 = most concerning/major barrier); mean scores are reported. Adverse events (AEs) of concern were selected from a prespecified list and respondents rank-ordered from most to least concerning by class. Physicians were also asked to gauge affordability and to rank-order 13 characteristics to identify key factors in prescribing preference. The impact of COVID-19 on aRCC care in practice was also assessed. Results: A total of 49 providers (84% community, 16% academic) treating a median of 20 (IQR 14–30) aRCC patients from across the United States participated. For IO-IO, the top 3 concerns in prescribing were AEs (4.3), patient out-of-pocket costs (OOP; 3.7), and unexpected late AEs (3.6), whereas patient OOP (4.3), AEs (4.1), and patient adherence (3.9) were of most concern for IO-TKI. For SA-TKIs, the top 3 concerns were patient adherence (3.9), patient OOP (3.9), and AEs (3.6). High patient OOP and impact on quality of life were the top 2 barriers in using IO-TKI therapy. The most concerning AEs were colitis, pneumonitis, and hypertension for IO-IO or IO-TKI, and diarrhea, fatigue, hand-foot syndrome, and hypertension for SA-TKI. Overall survival (OS), progression-free survival (PFS), and complete response (CR) were ranked 1st, 2nd, and 3rd factors in prescribing preferences while patient compliance, patient preference, and practice reimbursement ranked 11th, 12th, and 13th. Patient OOP and drug acquisition costs (DAC) were the most important factors when considering the affordability of treatment, with the perception that IO-IO was the most expensive among the classes of therapy. The overall impact of COVID-19 on caring for aRCC patients was very limited, with a moderate increased use of telemedicine and a slight impact on the timing and number of routine care visits. Conclusions: OS, PFS, and CR ranked highest among the most important factors influencing selection of 1L treatment for aRCC. Factors of concern and barriers varied by class of treatment, with patient adherence and OOP affecting use of TKI or IO-TKI therapies, and AEs affecting the use of IO-based therapy. This study revealed perceptions of high patient OOP and DAC of IO-IO therapy, in contrast to our expectations.

Temporal trends of adverse events and costs of nivolumab plus ipilimumab versus sunitinib in advanced renal cell carcinoma

Aims: To assess grade 3/4 adverse events (AEs) and costs of first-line nivolumab plus ipilimumab (NIVO + IPI) versus sunitinib in advanced or metastatic renal cell carcinoma. Methods: Individual patient data from the all treated population in the CheckMate 214 trial (NIVO + IPI, n = 547; sunitinib, n = 535) were used to calculate the number of AEs. AE unit costs were obtained from US 2017 Healthcare Cost and Utilization Project and inflated to 2020 values. Results: The proportion of patients experiencing grade 3/4 AEs decreased over time. Patients who received NIVO + IPI had lower average per-patient all-cause grade 3/4 AE costs versus sunitinib (12-month: US$15,170 vs US$20,342; 42-month: US$19,096 vs US$27,473). Conclusion: Treatment with NIVO + IPI was associated with lower grade 3/4 AE costs than sunitinib.

Treatment-free Survival after Immune Checkpoint Inhibitor Therapy versus Targeted Therapy for Advanced Renal Cell Carcinoma: 42-Month Results of the CheckMate 214 Trial

PURPOSE

Patients discontinuing immuno-oncology regimens may experience periods of disease control without need for ongoing anticancer therapy, but toxicity may persist. We describe treatment-free survival (TFS), with and without toxicity.

PATIENTS AND METHODS

Data were analyzed from the randomized phase III CheckMate 214 trial of nivolumab plus ipilimumab (n = 550) versus sunitinib (n = 546) for treatment-naïve, advanced renal cell carcinoma (aRCC). TFS was estimated by the 42-month restricted mean times defined by the area between Kaplan-Meier curves for two time-to-event endpoints defined from randomization: time to protocol therapy cessation and time to subsequent systemic therapy initiation or death. TFS was subdivided as TFS with and without toxicity by counting days with ≥1 grade ≥3 treatment-related adverse event (TRAE).

RESULTS

At 42 months since randomization, 52% of nivolumab plus ipilimumab and 39% of sunitinib intermediate/poor-risk patients were alive; 18% and 5% surviving treatment-free, respectively. Among favorable-risk patients, 70% and 73% of nivolumab plus ipilimumab and sunitinib patients were alive; 20% and 9% treatment-free. Over the 42-month period, mean TFS was over twice as long after nivolumab plus ipilimumab than sunitinib for intermediate/poor-risk (6.9 vs. 3.1 months) and three times as long for favorable-risk patients (11.0 vs. 3.7 months). Mean TFS with grade ≥3 TRAEs was a small proportion of time for both treatments (0.6 vs. 0.3 months after nivolumab plus ipilimumab vs. sunitinib for intermediate/poor-risk, and 0.9 vs. 0.3 months for favorable-risk patients).

CONCLUSIONS

Patients initiating first-line nivolumab plus ipilimumab for aRCC spent more survival time treatment-free without toxicity versus those on sunitinib, regardless of risk group.

Real-world outcomes in patients with metastatic renal cell carcinoma treated with first-line nivolumab plus ipilimumab

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Background: Nivolumab plus ipilimumab (NIVO+IPI), a first-in-class combination immunotherapy, was approved by the US Food and Drug Administration in April 2018 for the treatment of intermediate- or poor-risk advanced renal cell carcinoma (RCC), and the treatment paradigm has changed dramatically over the past few years. This real-world study examined treatment patterns and sequences, treatment response, safety, and survival outcomes with this novel first-line (1L) combination therapy among patients diagnosed with metastatic RCC (mRCC) in a community oncology practice setting. Methods: A retrospective analysis of the US Oncology Network’s iKnowMed medical data examined adult patients with an International Metastatic Renal Cell Carcinoma Database Consortium (IMDC) prognosis of intermediate- or poor-risk clear cell mRCC who received 1L NIVO+IPI between April 1, 2018, and March 31, 2020. Baseline demographic and clinical characteristics, treatment patterns, and treatment sequence were examined descriptively. Overall survival (OS), progression-free survival (PFS), objective response rate (ORR), duration of response (DoR), time to treatment discontinuation (TTD), and time to treatment response (TTR) were analyzed using the Kaplan–Meier method. Treatment-related adverse events (TRAEs) and healthcare resource utilization were also analyzed. Results: A total of 193 adults with stage IV mRCC treated with 1L NIVO+IPI were identified. Median age (range) was 63 (30.0–89.0) years, 73.1% were male, 69.4% were white, 56.7% were IMDC intermediate risk, and 60.6% had a documented Eastern Cooperative Oncology Group performance status of 0 or 1. Median follow-up time (range) was 9.7 (0.1–24.7) months. Median PFS (95% CI) was 17.1 (12.6–21.2) months, and the 1-year landmark PFS rate was 58.3% (50.4–65.4). At 12 months, the OS rate (95% CI) was 75.4% (67.8–81.4). The ORR (95% CI) was 43.2% (34.6–52.1) among patients with a response assessment; the median TTR (range) was 2.8 (0.3–4.1) months and median DoR was not reached. Median TTD (95% CI) was 5.8 (4.5–7.5) months. Among the 63 (31.3%) patients who received second-line therapy, 50.8% received cabozantinib and 12.7% received pazopanib. TRAEs were reported in 47.2% of patients—the most frequently reported were fatigue (13.5%), rash (10.4%), diarrhea (6.7%), nausea (6.2%), colitis (3.6%), and pruritus (3.6%). The treatment-related hospitalization rate was 5.5% and the emergency department visit rate was 3.1%. Conclusions: This real-world study supports the clinical efficacy of 1L NIVO+IPI for patients with mRCC. Our findings also suggest that the NIVO+IPI combination was generally well tolerated in the real-world setting, with low rates of adverse events and healthcare resource utilization.

Efficacy outcomes of nivolumab + cabozantinib versus pembrolizumab + axitinib in patients with advanced renal cell carcinoma (aRCC): Matching-adjusted indirect comparison (MAIC)

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Background: Nivolumab in combination with cabozantinib (N+C) has demonstrated significantly improved progression-free survival (PFS), objective response rate (ORR), and overall survival (OS), compared with sunitinib as a first-line (1L) treatment for aRCC in the phase 3 CheckMate (CM) 9ER trial. As there are no head-to-head trials comparing N+C with pembrolizumab in combination with axitinib (P+A), this study compared the efficacy of N+C with P+A as 1L treatment in aRCC. Methods: An MAIC was conducted using individual patient data on N+C (N = 323) from the CM 9ER trial (median follow-up: 23.5 months) and published data on P+A (N = 432) from the KEYNOTE (KN)-426 trialof P+A (median follow-up: 30.6 months). Individual patients within the CM 9ER trial population were reweighted to match the key patient characteristics published in KN-426 trial, including age, gender, previous nephrectomy, International Metastatic RCC Database Consortium risk score, and sites of metastasis. After weighting, hazards ratios (HR) of PFS, duration of response (DoR), and OS comparing N+C vs. P+A were estimated using weighted Cox proportional hazards models, and ORR was compared using a weighted Wald test. All comparisons were conducted using the corresponding sunitinib arms as an anchor. Results: After weighting, patient characteristics in the CM 9ER trial were comparable to those in the KN-426 trial. In the weighted population, N+C had a median PFS of 19.3 months (95% CI: 15.2, 22.4) compared to a median PFS of 15.7 months (95% CI: 13.7, 20.6) for P+A. Using sunitinib as an anchor arm, N+C was associated with a 30% reduction in risk of progression or death compared to P+A, (HR: 0.70, 95% CI: 0.53, 0.93; P = 0.015; table). In addition, N+C was associated with numerically, although not statistically, higher improvement in ORR vs sunitinib (difference: 8.4%, 95% CI: -1.7%, 18.4%; P = 0.105) and improved DoR (HR: 0.79; 95% CI: 0.47, 1.31; P = 0.359). Similar OS outcomes were observed for N+C and P+A (HR: 0.99; 95% CI: 0.67, 1.44; P = 0.940). Conclusions: After adjusting for cross-trial differences, N+C had a more favorable efficacy profile compared to P+A, including statistically significant PFS benefits, numerically improved ORR and DoR, and similar OS.[Table: see text]