Efficacy of ciclosporin monotherapy in non‐severe aplastic anaemia not requiring transfusions: Results from a multicentre phase <scp>II</scp> study

The efficacy of ciclosporin (CsA) to treat transfusion-independent non-severe aplastic anaemia (TI-NSAA) has not yet been systematically evaluated. We conducted a prospective trial in patients with TI-NSAA treated with CsA monotherapy. CsA (3.5 mg/kg/day) was administered to patients with TI-NSAA aged ≥16. The CsA dose was adjusted to maintain a blood CsA level of ≥600 ng/mL at 2 h post-administration. Blood cell counts were assessed after 8, 16 and 52 weeks of therapy. Thirty-two evaluable patients from 21 institutions were enrolled. The median age was 63.5 (range: 16-83) years. At 8 weeks, haematological improvement, with increases in haemoglobin (Hb) ≥1.5 g/dL (haematological improvement in erythrocytes [HI-E]) and platelet count ≥30 × 10⁹/L (haematological improvement in platelets [HI-P]), was observed in 0/25 (0%) and 6/32 (19%) evaluable cases respectively. HI-E and HI-P occurred in 1/25 (4%) and 10/32 (31%) patients at 16 weeks, respectively, and at 52 weeks in 5/25 (20%) and 16/32 (50%) patients respectively. Nine grade 3 adverse events (AEs) occurred in six patients, but there were no grade ≥4 AEs. Ten of the 32 patients experienced grade 2 renal toxicity. Low-dose CsA is effective in TI-NSAA patients and demonstrates minimal renal toxicity. However, at least 16 weeks are necessary to adequately evaluate its efficacy.