選択的アンドロゲン受容体モジュレーター（SARM）は臨床応用されるか？

Selective androgen receptor modulators (SARMs) are a novel class of compounds engineered to confer the anabolic benefits of testosterone such as increased muscle and bone mass while minimizing undesirable androgenic effects. Their tissue-selective activity and oral availability have sparked significant interest in their potential applications for conditions like muscle wasting, osteoporosis, hypogonadism, and frailty. We outline the chemical underpinnings of SARMs, their clinical promise, and the major challenges that have limited their regulatory approval to date. Although multiple SARMs have shown efficacy in increasing lean body mass in clinical trials, few have demonstrated consistent improvements in functional outcomes such as strength or mobility. Safety concerns, particularly regarding hepatotoxicity and cardiovascular risk, remain incompletely resolved. Nevertheless, a subset of SARMs is being actively evaluated for indications directly related to aging and sarcopenia. We conclude that SARMs are likely to enter clinical practice in select niches of men and women, especially among the frail, the elderly, or individuals with excessive loss of lean body mass. However, widespread approval will depend on future trials demonstrating both efficacy and long-term safety.