Table 2.

Phosphodiesterase Inhibitors.

Immunotherapy	Potential Immune Target	Animal Study Findings	Human Study Findings	References
Phosphodiesterase (PDE) Inhibitors:
Ibudilast	PDE3 − 4–10 & − 11	↓ ethanol consumption	↓ alcohol craving ↑ mood outcomes ↓ heavy drinking days clinical trial underway: NCT03594435 completed clinical trials: NCT03489850 NCT02025998	(Bell et al., 2015) (Ray et al., 2017) (Grodin et al., 2021)
Rolipram	PDE4	↓ ethanol intake and preference	–	(Hu et al., 2011) (Wen et al., 2012) (Blednov et al., 2014) (Franklin et al., 2015) (Gong et al., 2017) (Ozburn et al., 2020)
Mesopram	PDE4	↓ ethanol intake and preference	–	(Blednov et al., 2014)
Piclamilast	PDE4	↓ ethanol intake and preference	–	(Blednov et al., 2014)
CDP840	PDE4	↓ ethanol intake and preference	–	(Blednov et al., 2014)
Apremilast	PDE4	↑ ethanol-inducedsedation and intoxication no effect on ethanol CPP or withdrawal ↓ ethanol intake and preference	clinical trial completed: NCT03175549	(Blednov et al., 2018) (Blednov et al., 2018)
Rofumilast	PDE4	↓ ethanol intake and preference	–	(Liu et al., 2017)
TP-10	PDE10	↓ relapse-like alcohol self-administration	–	(Logrip et al., 2014)

Note. CPP = conditioned place preference