Use of pkc inhibitors in transplantation

A method of treating, preventing or delaying insulin-producing cell rejection comprising administering an effective amount of a PKC inhibitor of formula (I) or (IIa),

• wherein
• Ra is H;
• C1-4alkyl;
• or C1-4alkyl substituted by OH, NH2, NHC1-4alkyl or N(di-C1-4alkyl)2;
• and
• R is a radical of formula (a) or (b)
• wherein
• each of R1 and R11 is a heterocyclic residue;
• NR4R5 wherein R4 and R5 form together with the nitrogen atom to which they are bound a heterocyclic residue;
• each of R2, R3, R12 and R13, independently, is H, halogen, C1-4alkyl, CF3, OH, SH, NH2, C1-4alkoxy, C1-4alkylthio, NHC1-4alkyl, N(di-C1-4alkyl)2 or CN;
• and
• ring A is optionally substituted,
• R1a is
• wherein either s′ is 0 and R′12 is hydrogen or C1-4alkyl;
• or s′ is 1 and R′12 is pyridyl, preferably 2-pyridyl, and
• R′1a is hydrogen or C1-4alkyl,
• or a pharmaceutically acceptable salt thereof to a subject in need of such treatment, prevention or delay.