Darolutamide nears EU approval for mHSPC

The European Medicines Agency’s Committee for Medicinal Products for Human Use (CHMP) has recommended approval of darolutamide (Nubeqa) for use in combination with docetaxel and androgen deprivation therapy (ADT) for the treatment of patients with metastatic hormone-sensitive prostate cancer (mHSPC).¹

The oral androgen receptor inhibitor darolutamide is already approved in the United States for use in patients with mHSPC.

The CHMP’s recommendation is based on the placebo-controlled phase 3 ARASENS trial (NCT02799602), which showed that adding darolutamide to standard ADT and docetaxel boosted overall survival (OS) versus ADT/docetaxel alone in patients with mHSPC.

Results reported at the 2022 Genitourinary Cancers Symposium² and simultaneously published in the New England Journal of Medicine³ showed that at a median follow-up of 43.7 months for darolutamide plus ADT/docetaxel and 42.4 months with placebo plus ADT/docetaxel, the active therapy resulted in a 32.5% reduction in the risk of death (HR 0.68; 95% CI 0.57-0.80; P <.001).

The European Commission will now review the application for darolutamide and make a final decision on this indication in the coming months.

In the ARASENS trial, patients with cytologically confirmed metastatic adenocarcinoma of the prostate were eligible for the trial. All participants needed to be candidates for ADT and docetaxel, have an ECOG performance status of 0 or 1, and have adequate organ function.

Patients were randomized 1:1 to either 600 mg of daily darolutamide (n = 651) or matched placebo (n = 655) plus ADT/docetaxel. Factors for stratification included extent of disease (M1b/b/c) and alkaline phosphatase (ALP) levels. The primary end point was OS with secondary outcome measures of time to CRPC, time to pain progression, time for first symptomatic skeletal event (SSE), time to initiation of subsequent systemic antineoplastic therapy, and safety.

Patient characteristics were well balanced between the 2 groups. The median age was 67 years for both the darolutamide and placebo groups and most patients had a Gleason score of 8 or greater (77.6% vs 78.9%, respectively) and M1 stage (85.7% vs 86.5%) at initial diagnosis. At initial screening, patients in both groups were most likely to have M1b stage disease (79.4% vs 79.5%) and ALP levels equal to or above the upper limit of normal (55.5% each).

Median OS in the darolutamide arm was not estimable (NE; 95% CI, NE-NE) vs 48.9 months (95% CI, 44.4-NE) with placebo. Rates of OS at 48 months were 62.7% and 50.4%, respectively. The effect of active therapy was consistent across patient subgroups, including by ALP level below (HR, 0.64; 95% CI, 0.46-0.88) or above the upper limit of normal (HR, 0.69; 95% CI, 0.56-0.85), and by either de novo (HR, 0.71; 95% CI, 0.59-0.85) or recurrent (HR, 0.61; 95% CI, 0.35-1.05) metastatic disease status.

Moreover, darolutamide was associated with superior secondary outcomes despite patients in this arm receiving fewer subsequent life-prolonging systemic antineoplastic therapies (56.8%) vs the placebo arm (75.6%). Common subsequent therapies included abiraterone acetate (35.6% vs 46.9%), enzalutamide (Xtandi; 15.2% vs 27.5%), cabazitaxel (Jevtana; 18.1% vs 18.0%), and docetaxel (14.6% vs 18.0%). Notably, 66% of patients in the placebo arm went on to receive life-prolonging therapy with an AR pathway inhibitor. Time to first subsequent antineoplastic therapy was NE (95% CI, NE-NE) in the active therapy arm vs 25.3 months (95% CI, 23.1-28.8) in the placebo group (HR, 0.39; 95% CI, 0.33-0.46; P <.001).

A significant delay in time to castration-resistant disease was noted in the darolutamide vs placebo groups, at NE (95% CI, NE-NE) vs 19.1 months (95% CI, 16.5-21.8), respectively (HR, 0.36; 95% CI, 0.30-0.42; P <.001). Darolutamide was also associated with increased time to pain progression at NE (95% CI, 30.5-NE) vs 27.5 months (95% CI, 22.0-36.1) with placebo (HR, 0.79; 95% CI, 0.66-0.95; P = .01). Time to first SSE was NE in both arms, but statistically significant benefit with the darolutamide combination was noted (HR, 0.71; 95% CI, 0.54-0.94; P = .02).

Rates of treatment-emergent adverse events (AEs) were similar between arms, at 99.5% with the darolutamide regimen and 98.9% with placebo. Consistent with prior clinical experience in other settings, darolutamide had a favorable safety profile. The rates of any treatment-emergent adverse event, serious adverse event, and adverse events leading to permanent discontinuation of study treatment were similar between the darolutamide and the placebo groups.

Grade 3/4 AEs occurring with darolutamide and placebo included neutropenia (33.7% vs 34.2%, respectively), febrile neutropenia (7.8% vs 7.4%), hypertension (6.4% vs 3.2%), and anemia (4.8% vs 5.1%). After adjusting for differences in drug exposure, the was no difference in the occurrence of AEs of special interest for AR pathway inhibitors between groups, including events such as fatigue, bone fractures, rash, falls, hypertension, and cardiac disorders.

References

1. Positive CHMP opinion for darolutamide in combination with docetaxel for the treatment of metastatic hormone-sensitive prostate cancer. Published online and accessed January 27, 2023. https://bit.ly/3RnKihj

2. Smith MR, Hussain MHA, Saad F, et al. Overall survival with darolutamide versus placebo in combination with androgen-deprivation therapy and docetaxel for metastatic hormone-sensitive prostate cancer in the phase 3 ARASENS trial. J Clin Oncol. 2022;40(suppl 6):abstr 13. doi: 10.1200/JCO.2022.40.6_suppl.013

3. Smith MR, Hussain MHA, Saad F, et al. Darolutamide and survival in metastatic, hormone-sensitive prostate cancer. N Engl J Med. Published online February 17, 2022. doi: 10.1056/NEJMoa2119115