Drug Combos May Help Lower Blood Pressure in Patients Taking Imbruvica

Treatment with Imbruvica (ibrutinib) or other BTK inhibitors may make patients more likely to experience high blood pressure, but a combination treatment with two or more blood pressure drugs may help in reducing patients’ blood pressure, according to a recent study whose findings were published in Blood Advances.

“To our knowledge, this is the first and only study to examine how to optimally treat high blood pressure in patients receiving (Imbruvica),” study senior author, Dr. Mazyar Shadman, of Fred Hutchinson Cancer Center and the University of Washington School of Medicine, said in a news release. “Our findings strongly suggest that aggressive treatment with certain combinations of antihypertensive medications can achieve significantly reduced blood pressures in this patient population.”

Imbruvica is a type of drug called a Bruton’s tyrosine kinase (BTK) inhibitor and is used to treat blood cancers such as chronic lymphocytic leukemia (CLL) and small lymphocytic lymphoma (SLL). However, according to the American Society of Hematology, patients treated with Imbruvica are prone to developing new or worsening high blood pressure (hypertension).

“One study found this to be the case in over 78% of patients treated with ibrutinib over a median of 30 months,” study author, Dr. Laura Samples, of the Fred Hutchinson Cancer Center and University of Washington School of Medicine, said in the release. “Uncontrolled high blood pressure, or hypertension, can lead to major adverse cardiovascular events, such as heart attack, heart failure and stroke.”

The researchers analyzed the medical records of 196 patients who were undergoing treatment with a BTK inhibitor and one or more blood pressure (antihypertensive) medications for at least three months. The majority (approximately 93%) of patients were Caucasian and the average age was 67. Seventy-one percent were male, and 29% were female.

Notably, nearly all (90%) of patients in the study were being treated with Imbruvica.

“Studies suggest that patients taking these newer agents still face an increased risk of major adverse cardiovascular events, although the risk may be lower than that of (Imbruvica),” Dr. Samples said.

Patient data was divided into two categories: those who were taking one or more antihypertensive medications before starting a BTK inhibitor (118 patients) and those who began taking one or more hypertensive mediation after starting BTK inhibition (78 patients).

Findings showed that patients in the prior hypertensive medication group who took beta blockers and hydrochlorothiazide — both types of high blood pressure medications — tended to experience significant reductions in the average reduction of mean arterial pressure. Additionally, patients who started blood pressure medication after BTK inhibition saw similar improvements in mean arterial pressure when they took an ACE inhibitor or ARB plus hydrochlorothiazide.

“Our results reinforce that — in this patient population as in patients with hypertension in general — you need to treat with multiple drugs to achieve successful blood pressure control,” said Dr. Samples.

The study did not investigate why these combinations of antihypertensive medication were beneficial, but that question could lead the way for future research, according to the authors.

“But we now have some data that other researchers can analyze to perhaps find answers to these questions,” Shadman said.

“Given that increased blood pressure is a ‘class effect’ of treatment with BTKis, both doctors and patients need to be aware of this risk and patients’ blood pressure should be monitored regularly so that treatment can begin immediately when an increase is detected,” Samples said.

For more news on cancer updates, research and education, don’t forget to subscribe to CURE®’s newsletters here.