Table 1.

NRTI cellular transport and half-lifes.

NRTI Name	Diffusion/SLC Transporter [Ref.]	Active ddNTP & ddNDP analogue	Plasma Half-Life [Ref.]	Inn a cellular half-life [Ref.]
Lamivudine (3TC)	OCT1, OCT2, CNT1 [24, 25, 27]	3TC-TP	22 h [26]	15 to 16 h [29]
Emtricitabine (FTC)	MATE1 [30]	FTC-TP	37 h [31]	39 h [31]
Tenofovir Disoproxil Funiarate (TDF)	Direct diffusion [32]	TFV-DP	∼17h [33]	164 h [31]
Tenofovir Alafenamide (TAF)	Direct diffusion [32]	TFV-DP	∼125 h [33]	164 h [31]
Abacavir (ABC)	Direct diffusion [18]	CBV-TP	∼3.3 [34]h	∼18 to 21 h [35]
Zidovudine (AZT)	OAT1-4, CNT1, CNT3, ENT2	AZT-TP	∼2 h [36]	∼9 h [37]
Didanosine (ddI)	CNT2, CNT3, ENT1, ENT2 [23, 38]	ddI-TP	2.3 h [39]	24 h to 40 h [40]
Stavudine (d4T)	CNT1 [41] and. Direct diffusion [19]	d4T-TP	7 h [42]	4.5 h [43]

CNT, concentrative nucleoside transporter; ENT, equilibrative nucleoside transporter; MATE, multidrug and toxin extrusion protein; OAT, organic anion transporter; OCT, organic cation transporter.