Here’s an interesting paper about successfully desensitizing a patient with an mTOR inhibitor allergy. I also experienced allergy-like and other inflammatory symptoms with low doses of weekly rapamycin, including itchy, pruritic rashes, like this patient. Others on weekly sirolimus/everolimus have developed pruritis as well, though it’s uncommon (including in Joan Mannick’s study ~ 4%).
Since mTOR inhibition was the only effective treatment for this patient’s condition, they desensitized her by reinitiating sirolimus at a super low dose of 0.1 mg/day followed by tiny dose escalations over long periods of time, along with an H1 agonist similar to Zyrtec. Eventually, she tolerated a dose of 0.5 mg/day with a trough concentration of 2 ng/mL without adverse reactions, and her condition improved and stabilized.
The paper also notes that while trough levels of 5-15 ng/mL are usually considered therapeutic (for certain medical conditions), low levels of 1-2 ng/mL can also be therapeutic.
They also mention a couple of other case reports of patients with allergy-like responses to sirolimus, one with anaphylaxis and another with pruritis. Even the patient with anaphylaxis was able to undergo rapid oral desensitization.
The conclusion was that mTOR inhibitor therapy should not necessarily be abandoned because of allergic reactions and that desensitization may be possible.
When I took 2-6 mg of rapamycin every 7-10 days for about 12 weeks, I developed pruritis, joint pains, lip bumps, and, later, elevated CRP with exacerbations of what I think is an immune-mediated recurrent myocarditis, first triggered by the Covid vaccine. The whole reason I was taking rapamycin was in an effort to rejuvenate my immune system and cure that condition, since conventional medicine has little to offer. So I am glad to see this paper. I plan to try again after a long break starting with 1 mg every 10-14 days or so, along with Zyrtec.
mTOR-inhibitor-allergy-desensitization-20240423-9443-11czyss.pdf (1.1 MB)