Primary progressive aphasia (PPA) is a neurodegenerative disorder characterized by progressive deterioration of language function. Currently, high-definition transcranial direct current stimulation (HD-tDCS), a non-invasive brain stimulation (NIBS) technique, and modified constraint-induced language therapy (mCILT), an intensive speech therapy, have each been shown to enhance language performance independently; however, their combined efficacy has not been thoroughly investigated. This study reports data from two participants in an ongoing clinical trial: one with logopenic variant PPA (lvPPA) and one with nonfluent/agrammatic variant PPA (naPPA). Using a crossover, double-blind, semi-randomized, sham-controlled study, both subjects completed two treatment arms of 10 HD-tDCS or sham stimulation sessions paired with mCILT, including baseline testing, post-treatment follow-ups, standard language assessments, and neuroimaging. Stimulation was administered at FT7 (left frontotemporal), which targets regions that have anatomical proximity and functional connectivity to both lvPPA's and naPPA's region of atrophy, the LTPJ and left posterior fronto-insular areas, respectively. The results align with such atrophy patterns as active stimulation led to significant improvements in at least one condition for both variants. Furthermore, these results revealed that combined therapy may be effective in lvPPA noun and verb performance as well as naPPA verb performance, although possibly requiring booster sessions, while mCILT alone may be effective at enhancing short-term noun performance and verb retention in lvPPA. Future work should explore optimal stimulation targets and parameters to maximize the benefits of HD-tDCS combined with mCILT across PPA subtypes.