Yes, guagua to Samana and then the "Purple Bus" that goes to Puerto Plata. They will let you off in Sosua.
From Puerto Plata to Samana, Transportes Papagayo 1-829-376-8346 or 1-809-749-6415 leaves Puerto Plata Hospital at 6:30 am once a day for Sanchez and Samana and returns from Samana at 2 p.m. They stop in front of Janet's Cabarete and will stop anywhere in Cabarete/Sosua or along the way if you call them (Spanish speaking Salvador). No Web Site, cost approx. 350 RD.