Kaletra Side Effects Linked To Bradycardia Risk: Study

As some researchers explore whether the HIV drug Kaletra may be considered a possible treatment for COVID-19, the findings of a new study suggest that side effects may cause bradycardia; causing a lowering of the heart rate to potentially dangerous levels.

French researchers say they have confirmed a causal link between Kaletra and bradycardia in a study of its effects on patients infected with the novel coronavirus, determining that it is a clinically significant risk. Their findings were published July 9 in the medical journal Circulation: Arrhythmia and Electrophysiology.

Kaletra (lopinavir/ritonavir) is an antiviral medication approved for the treatment of HIV infections in patients 14 days of age and older. It Is manufactured by Abbott Laboratories and was approved by the FDA in September 2000.

In an ongoing study in France to see whether Kaletra was effective in the treatment of COVID-19, researchers looked at its effects on 41 infectected patients in ICU. Of those, nine patients experienced heart rates which dropped below 60 beats per minute (bpm) for more than 24 hours.

According to their findings, eight of those nine patients suffered sinus bradycardia, while the ninth was found to have a third degree atrioventricular block.

The researchers said closer investigation virtually confirmed a causal connection, meaning they are fairly certain it is the Kaletra which caused the cases of bradycardia.

“One hypothesis is that the inflammatory damage associated with COVID-19 increases intestinal absorption of (Kaletra) in elderly patients and increase the risk of bradycardia. The change in (Kaletra) doses administered and the decrease of inflammation during hospitalization could explain the regression of bradycardia,” the researchers concluded. “Nevertheless, bradycardia could be a sign of severe cardiological or neurological impairment since it is associated with lymphopenia that seems to reflect the severity of COVID-19 infection.”

Some previous studies have warned that side effects of Kaletra, used to prevent the transmission of HIV from mothers to their unborn children, caused serious heart problems and other health issues in newborns.

In March 2011, the FDA issued a Kaletra drug safety communication, warning that premature babies could suffer serious heart, kidney or breathing problems if given the drug before their due date. A review of adverse events reported to the FDA revealed at least 10 cases of serious injuries that resulted from premature newborns being given Kaletra; one of which resulted in a child’s death due to cardiogenic shock.

It’s effectiveness as a COVID-19 treatment is still under investigation.