Amino acids (leucine/valine/isoleucine), codenamed TK-98, could be an adjuvant to conventional corticosteroid treatment of myositis and combat the muscle atrophy associated with it. Japanese researchers tested their efficacy in a randomized placebo-controlled trial conducted over three months and followed by an open-label phase
- 47 patients with polymyositis or dermatomyositis participated,
- a modest gain was observed on the global muscular strength (the main criterion of judgment, evaluated by manual testing) but without significant statistical value,
- only a slight functional improvement was noted in shoulder flexion.
The authors therefore do not recommend this treatment in this indication.
