How does tenofovir cause renal failure? The anti-HIV drug is primarily eliminated by the kidneys, which means there could be a link between tenofovir and renal toxicity. While most drugs are eliminated by the liver or kidneys, tenofovir is different because of dosing issues.

Common HIV medications that contain tenofovir disoproxil fumarate (TDF) include Viread, Truvada, Stribild, Complera and Atripla.

These drugs contain the active ingredient tenofovir disoproxil fumarate, which puts them in a class of medications called nucleoside reverse transcriptase inhibitors (NRTIs). Put simply, the drugs work by stopping the HIV virus from replicating itself. When the HIV virus can no longer perform its replication, the transmission of HIV is inhibited and the patient’s own immune system improves.

Link Between Tenofovir and Renal Toxicity

According to aidsmap.com, tenofovir “can build up to toxic levels in the renal tubules,” which are the parts of the kidney that form urine along and allow water and salts to be reabsorbed.

A patient who has pre-existing impaired kidney function or those who take high blood pressure medications are at an increased risk of suffering the effects of tenofovir and renal toxicity, according to a study of 1,500 patients.

In that study, 25 patients who were taking high blood pressure medication or other drugs that had the potential to negatively affect the kidneys incurred tenofovir toxicity. Without the additional medicinal factors, one patient out of 39 suffered from similar tenofovir toxicity.

At least one tenofovir lawsuit alleges that the drug has such a low absorption rate that the patient must ingest a higher dose for the medication to deliver the desired antiviral effect. This high dose enables the drug be effective against the HIV virus, but may cause kidney damage in the process.

At least one patient alleges tenofovir and renal toxicity caused him to develop Fanconi syndrome, which is a rare kidney disease that results in excessive releases of glucose, salts, uric acid, potassium and certain amino acids through the urine.

Lawsuits allege the extra tenofovir clogs the kidneys and damages bones, citing cases of osteopenia and osteoporosis developing among patients who previously had no history of bone density problems. Osteopenia is a term used for weakened bones; osteoporosis means bones have deteriorated to the point of become fragile and porous.

Even the side effect of bone problems can be attributed to tenofovir’s processing through the kidneys. Kidneys filter nutrients, separating water, glucose, amino acids, bicarbonate, urea and creatine along with potassium, calcium, sodium and phosphate.

If these substances are not reabsorbed properly (or appropriately eliminated), the results can cause not only kidney issues, but also chemical and nutritional imbalances.

Adding insult to injury, one tenofovir lawsuit alleges an improved version of the drug was discovered as far back as 2001. Pharmacy company Gilead, which makes Viread, purportedly developed tenofovir alafenamide fumarate (TAF), but allegedly withheld research results to make the most money it could from TDF.

The new tenofovir (TAF) is called Genvoya, and is apparently more bioavailable than TDF. With a better absorption rate, Genvoya would require lower dosages to be just as effective as higher doses of Viread and other TDF-based medications.