No there isn't
But you can take the Caribe Tour Bus to Saman? from POP.
Send KEN an email or a PM and ask him if that bus only goes from Sosua or does it also go from POP. He is one of the best informed people about that ride. Piece of cake but you have to get up in the morning, early...
Metro services Saman? directly from Santo Domingo but there are no places to intersect. I sometimes go to San Francisco de Macoris to leave packages for friends out there. There are nice littler buses that go from Santiago to Saman?, maybe 8 every day. No rigid schedule.
Good luck!
HB