Abatacept in Early Systemic Sclerosis (ASSET study) Save

An open-label extension of the ASSET trial (abatacept in diffuse cutaneous systemic sclerosis) showed continued safety with significant improvements in the modified Rodnan Skin Score (mRSS) at 12 months, suggesting abatacept (ABA) may benefit early systemic sclerosis (SSc).

ASSET was a phase 2, double-blind randomised trial, of ABA vs. placebo for 12 months. This report demonstrates findings from an open-label extension wherein PBO patients were transitioned to ABA (125 mg subcutaneous every week) for 6 months. The primary endpoint was the mRSS. 

In the randomized trial, 88 participants were randomly treated with either abatacept (n=44) or placebo (44); and 32 patients from each treatment group completed the 6-month open-label extension.

Improvement in the mRSS was:

• ABA: −6·6 (SD 6·4) at 12 months and -9.8 at the end of the open-label extension (month 18).
• PBO: -3.7 (SD 7·6) at 12 months  and −6·3 with 6 more mos of ABA out to month 18.

Adverse events were balanced between groups and there were 2 deaths in the abatacept group (scleroderma renal crisis) during the 12-month double-blind period. 

Further studies of abatacept in systemic sclerosis are awaited.