BMPR2 and Opportunistic infection: An advantage of targeting IL-1ß specifically is that this may mitigate against the risk of opportunistic infection by allowing other IL-1 to participate in host defence.20 Other recent research has shown that targeting inflammatory signaling in combination with increasing BMPR2 function is helpful in the treatment of PAH by the use in animal models of the drug FK506 (Tacrolimus)21 and a subsequent phase IIa clinical trial.22