Concentrations of ciclosporin, sirolimus (rapamycin) and tacrolimus may be increased when co-administered with Kaletra due to CYP3A inhibition by Kaletra. More frequent therapeutic concentration monitoring is recommended until plasma levels of these products have been stabilised.
Kaletra Summary of Product Characteristics, AbbVie Ltd, January 2021.

Coadministration may result in increased plasma concentrations of ciclosporin. Therapeutic concentration monitoring is recommended for immunosuppressants when coadministered with Kaletra.
Kaletra Prescribing Information, AbbVie Ltd, October 2020.

The pharmacokinetic interaction between Kaletra and ciclosporin was investigated in 3 HIV+ patients after liver transplant; ciclosporin pharmacokinetics were available in 2/3 patients prior to starting Kaletra and in all three patients 3-6 weeks after starting Kaletra. Prior to Kaletra, ciclosporin pharmacokinetic showed typical absorption and elimination characteristics (Tmax ~1 h, half-life 4-6 h) and were comparable to those obtained in HIV- subjects. Following the addition of LPV/RTV (400/100 mg twice daily), a marked alteration in the ciclosporin pharmacokinetic plasma profile was observed - absorption/elimination curves were flattened and there was little variation in concentrations over the 12 h profile. Tmax was delayed, Cmax reduced and half-life prolonged up to 38 h. To maintain target ciclosporin trough concentrations (75-125 ng/ml), dose reductions to 5-20% of the original dose were required.
Management of drug-to-drug interactions between cyclosporine A and the protease-inhibitor lopinavir/ritonavir in liver-transplanted HIV-infected patients. Vogel M, Voigt E, Michaelis HC, et al. Liver Transpl, 2004, 10: 939-44.

The interactions between ciclosporin and antiretrovirals were evaluated in 17 HIV+ liver and kidney transplant subject pre-transplant and at intervals up to 2 years post transplant. For those subjects receiving Kaletra, lopinavir AUCs were 5-6 times higher than literature values and ritonavir AUCs were up to 3x times higher. For subjects on protease inhibitors, ciclosporin dose had to be decreased by >75% to maintain ciclosporin AUC within range.Two year evaluation of the interactions between antiretroviral medication and cyclosporine in HIV+ liver and kidney transplant recipients.
Frassetto LA, Baloum M, Roland ME, et al. 10th Conference on Retroviruses and Opportunistic Infections, Boston, February 2003, abstract 540.