Foreign Service Benefit Plan, call Express Scripts at 1-800-922-8279 MHBP and Rural Carrier Benefit Plan, call CVS Caremark at 1-800-237-2767 -For precertificationof all other listeddrugs: Foreign Service Benefit Plan, call 1-800-593-2354 MHBP, call 1-800-410-7778 Rural Carrier Benefit Plan, call 1-800- -8432 Abraxane.