Tenofovir disoproxil fumarate has not been evaluated in patients receiving nephrotoxic medicinal products (e.g. aminoglycosides, amphotericin B, foscarnet, ganciclovir, pentamidine, vancomycin, cidofovir or interleukin-2). Use of tenofovir disoproxil fumarate should be avoided with concurrent or recent use of a nephrotoxic medicinal product. If concomitant use of tenofovir disoproxil fumarate and nephrotoxic agents is unavoidable, renal function should be monitored weekly.
Viread Summary of Product Characteristics, Gilead Sciences Ltd, September 2016.

Tenofovir-DF should be avoided with concurrent or recent use of a nephrotoxic agent. Since tenofovir-DF is primarily eliminated by the kidneys, coadministration of tenofovir-DF with drugs that reduce renal function or compete for active tubular secretion may increase serum concentrations of tenofovir and/or increase the concentrations of other renally eliminated drugs. Some examples include, but are not limited to, cidofovir, acyclovir, valacyclovir, ganciclovir, valganciclovir, aminoglycosides (e.g., gentamicin), and high-dose or multiple NSAIDs.
Viread Prescribing Information, Gilead Sciences International Inc, February 2016.

Methotrexate concentrations were determined in 43 HIV+ patients treated with ARVs and chemotherapy containing high dose methotrexate (3g/m2). Methotrexate elimination half-life was not affected by use of NNRTIs, integrase inhibitors or NRTIs (tenofovir /emtricitabine or abacavir/lamivudine).
The pharmacokinetics of high‑dose methotrexate in people living with HIV on antiretroviral therapy. Dalla Pria A, Bendle M, Ramaswami R, et al. Cancer Chemother Pharmacol, 2016, 77:653-657.