Rabbit antithymocyte globulin versus OKT3 induction therapy after heart-lung and lung transplantation: effect on survival, rejection, infection, and obliterative bronchiolitis

The superiority of different induction therapies after heart-lung and lung transplantation is not clearly established; specifically, whether monoclona l (OKT3) or polyclonal antibody induction therapy provides any advantage. B etween 1989 and 1991 we used induction therapy with either rabbit anti-thym ocyte globulin (RATG) or OKT3, given at random based on the availability of RATG. RATG was used in 25 patients (RATG group 1) and OKT3 in 38 patients (OKT3 group 1). Early results suggested a survival advantage with RATG. Fro m 1992 until 1997 we used RATG induction therapy in 108 patients (RATG grou p 2). This study analyzed longer-term survival, infection, rejection, and o bliterative bronchiolitis (OB) rates for RATG group 1 and OKT3 group 1 and assessed outcomes for RATG group 2. The 1-, 3-, and 5-year survival for RAT G group 1 was 72 %, 72 %, and 52 % and for OKT3 group I was 63 %, 49 %, and 34 % (P < 0.05). The 1- and 3-year survival for RATG group 2 was 84 % and 74 %. The 1-, 3-, and 5-year actuarial freedom rates from lung rejection fo r RATG group 1 were 38 %, 38 %, and 31 % and for OKT3 group I were 21 %, 0 %, and 0 % (P < 0.01). The linearized rate (events/100 patient days) of all infections at 3 months was 1.55 +/- 0.28 for RATG group 1 and 2.19 +/- 0.2 7 for OKT3 group 1 (P = NS). The infection rate for RATG group 2 was 1.60 /- 0.13. The actuarial rates of freedom from OB at 1, 3, and 5 years for RA TG group 1 were 84 %, 51 %, and 45 % and for OKT3 group 1 were 77 %, 61 %, and 36 % (P = NS), while for RATG group 2 the rates were 97 and 92 % at 1 a nd 3 years (P < 0.01 vs RATG group 1 and OKT3 group 1). The use of RATG ind uction therapy from 1989 through 1991 resulted in improved actuarial surviv al and less rejection, without increased infection rates. The use of RATG s ince 1992 has continued to result in similar outcomes for survival, infecti on, and rejection. The time to onset of OB has improved further in recent y ears. This may be a result of recent improvements in cytomegalovirus (CMV) prophylaxis.