New Zealand national retrospective cohort study of survival outcomes of patients with metastatic melanoma receiving immune-checkpoint inhibitors

BACKGROUND

Immune checkpoint inhibitors (ICIs) have increased overall survival (OS) in metastatic melanoma in all clinical trials to date. However, pivotal trial populations were not representative of the real-world population in New Zealand. Real-world treatment effectiveness studies help evaluate the value of public pharmaceutical expenditure.

AIM

To determine the survival outcomes of New Zealand patients with unresectable or metastatic melanoma treated with pembrolizumab or nivolumab.

METHODS

This is a national retrospective cohort study. Patients with advanced unresectable or metastatic melanoma who received publicly funded immune-checkpoint inhibitors (ICIs) from 2017 to 2019 were included. Individual patient data were extracted from national administrative databases. The primary endpoint was OS, and secondary endpoints included OS by age, duration of treatment, posttreatment survival, and 30-day mortality from last pharmaceutical claim.

RESULTS

Five hundred ninety-seven patients were included, with a median follow-up of 25 months. One-year OS was 72%, the 2-year OS estimate was 60%, and median OS not reached. Survival did not differ by dichotomized age (≥70 vs. <70 year old), hazard ratio (HR) .94 (95% confidence interval (CI): .72-1.22; p = .62). Median duration of treatment was 9.0 months (95% CI: 7.9-10.1). Median post-treatment survival for the subgroup who had ceased treatment was 12.0 months (95% CI: 9.0-14.0). For the sample as a whole, the estimated 30-day mortality from last pharmaceutical claim was 15.7%.

CONCLUSION

OS in our New Zealand real-world population is comparable to pivotal clinical trials and real-world data (RWD) from other countries. These findings support the achievement of health gains from use of ICI in advanced unresectable and metastatic melanoma.

Efficacy of immune-checkpoint inhibitors (ICI) in the treatment of older adults with metastatic renal cell carcinoma (mRCC) - an International mRCC Database Consortium (IMDC) analysis

OBJECTIVE

Older adults with metastatic renal cell carcinoma(mRCC) are underrepresented in immune-checkpoint inhibitor(ICI) registration trials. Here we compare the efficacy of ICI treatments in older vs. younger adults with mRCC.

METHODS

Using the International mRCC Database Consortium(IMDC), patients treated with a PD(L)-1 based ICI were identified. Older adult was defined as ≥70-years at the time of treatment. Descriptive statistics were summarized in means, medians, and proportions. Effectiveness endpoints included overall survival (OS), time-to-treatment failure(TTF), time-to-next treatment(TNT), and overall response rate(ORR). Hazards ratios were adjusted(aHR) for IMDC risk factors, histology, line of treatment and older age.

RESULTS

Of 1427 included patients, 397(28%) were older adults. ICI was used as 1st line(1 L) in 40%, 2nd line(2 L) in 49% and 3rd line(3 L) in 11% of patients. In univariable analysis, older adults had inferior OS compared to younger adults(25.1 m vs. 30.8 m, p < 0.01). There were no significant differences in TTF (6.9 m vs. 6.9 m, p = 0.4) or TNT(9.1 m vs 10 m, p = 0.3) between groups. In multivariable analyses, older age was not independently associated with worse OS(aHR = 1.02, p = 0.8), TTF(aHR = 0.95, p = 0.6) or TNT(aHR = 0.93, p = 0.5). Older adults had a lower ORR compared to younger adults(24% vs. 31%, p = 0.01), which was mainly driven by responses in 1 L(31% vs. 44%, p = 0.02) and not observed in 2 L/3 L.

CONCLUSIONS

After multivariable analyses, older adults with mRCC treated with ICI had no difference in OS, TTF or TNT when compared to younger adults. Our data support that chronological older age should not preclude patients from receiving ICI based therapies.