Healthfirst Leaf Plans. Healthfirst Leaf Plans; P.O. Box 95000-5645; Philadelphia, PA 19195-5645; Healthfirst Essential Plan. Healthfirst Essential Plan; P.O. Box 95000-5645; Philadelphia, PA 19195-5645; Healthfirst CompleteCare (HMO SNP) Healthfirst CompleteCare; P.O. Box 95000-5170; Philadelphia, PA 19195-5645; Healthfirst Medicare Advantage ....