Bioequivalence and Food Effect Assessment of Apalutamide Tablets Relative to Erleada in Healthy Chinese Male Participants

Apalutamide, a second-generation non-steroidal androgen receptor inhibitor, is indicated for the treatment of non-metastatic castration-resistant and metastatic hormone-sensitive prostate cancer. A study was conducted to investigate the pharmacokinetic (PK) parameters of apalutamide in healthy Chinese male participants and to evaluate the bioequivalence (BE) of the test and reference formulations (Erleada) under both fed and fasted conditions. This study was a single-center, open-label, randomized, single-dose, two-period, two-sequence, crossover study. A total of 88 healthy Chinese male volunteers were enrolled in this study, with 32 assigned to the fasted study and 56 to the fed study. The subjects were administrated a single dose of either the test or the reference formulation in each treatment period. The PK parameters of apalutamide, including the time to peak (Tmax), peak concentration (Cmax), and the area under the concentration-time curve from time 0 to 72 h (AUC0-72 h), were calculated, and the safety of apalutamide was also assessed. The Cmax and AUC0-72 h values were comparable between the test and reference formulations under both fasted and fed conditions. The 90% confidence intervals (CIs) for Cmax and AUC0-72 h fell within the BE acceptance range of 80.00% to 125.00% under both conditions. However, Tmax in the fed condition was slightly different, with median values of 4.5 h for the test formulation and 3.5 h for the reference formulation. No serious adverse events occurred during the study, and both formulations were well tolerated under fasted and fed conditions. The test and reference formulations of apalutamide were demonstrated to be bioequivalent under both fasted and fed conditions, and were well tolerated with favorable safety profiles.