Maraviroc 300 mg twice daily and NRTIs can be co-administered without dose adjustment. Co-administration of maraviroc (300 mg twice daily) with lamivudine/zidovudine (150/300 mg twice daily) showed no effect of maraviroc on lamivudine AUC (13% increase) or Cmax increased 16%. Maraviroc concentrations were not measured, but no effect is expected.
Celsentri Summary of Product Characteristics, ViiV Healthcare, September 2018.

The recommended dose of maraviroc when coadministered with NRTIs is 300 mg twice daily. Maraviroc had no effect on the pharmacokinetics of lamivudine.
Selzentry Prescribing Information, ViiV Healthcare, July 2018.

The effect of maraviroc (300 mg twice daily) on lamivudine/zidovudine (150/300 mg, twice daily) was studied in 11 healthy volunteers. Lamivudine AUC and Cmax increased by 14% and 16%, respectively. Zidovudine AUC and Cmax decreased by 2% and 8%, respectively. These changes in NRTI exposure are not clinically significant.
Effect of maraviroc on the pharmacokinetics of midazolam, lamivudine/zidovudine, and ethinylestradiol/levonorgestrel in healthy volunteers. Abel S, Russell D, Whitlock L, et al. Br J Clin Pharmacol, 2008, 65(S1): 19-26.