Drost Rome 104, known to him only from
officina T=3 like yours, in three specimens.
However
his illustrated specimen, pl. 34, shows the captive on
reverse seated and looking right, not turning
his head back to look at the emperor, as on your piece.
Apparently the description of this coin in
RIC 220 is incomplete, omitting mention of the captive before
Mars, for
Drost records no examples without captive, and cites
RIC 220 for the variant
with captive.
RIC 220 cites the BM
collection, obviously a coin that would have been known to
Drost, if it really omitted the captive as
RIC states.
