Platelet-rich plasma is basically activating concentrated platelet cells to produce large amounts of growth factors. These are necessary for healing and regeneration and growth of tissue. In fact, platelet-rich plasma therapy (PRP) is popular overseas with facial skin texture and complexion rejuvenation.
To answer your question, yes. It is safe while you are on Accutane as it is purely your own blood by-products. In addition, it stimulates healing and growth [1]. In fact, its effects may be even better as Accutane makes your skin more able to absorb the growth factors of PRP.
1. Everts PAM, Knape JTA, Weibrich G, et al. Platelet-rich plasma and platelet gel: a review. The journal of extra-corporeal technology. 2006;38(2):174-187. . Accessed November 19, 2019.