Positives

• In the ACTIV-1 immunomodulator trial, hospitalized COVID-19 patients receiving abatacept had a substantial 38% reduction in 28-day all-cause mortality compared with placebo medRxiv.
  
  

Negatives

• The ACTIV-1 abatacept substudy did not meet its primary time-to-recovery endpoint, indicating that benefits may be limited to severe inflammatory subsets rather than broad post-acute populations Icts.
  
  
• Published Long COVID trials of abatacept are not yet available, so off-label use rests on autoimmune extrapolation rather than direct PASC efficacy data NIH.
  
  

Hurdles & Side Effects

• Abatacept (Orencia) requires monthly IV infusions or weekly subcutaneous injections at roughly $4,000+ per month, with strict insurer prior authorization tied to RA, JIA, or psoriatic arthritis diagnoses Uptodate.