麻豆传媒

Chewing the loading dose of ticagrelor (Brilinta), instead of swallowing it whole, boosted early platelet inhibition during primary percutaneous coronary intervention (PCI) in a small randomized trial.

When 50 consecutive patients at a large tertiary care center were randomized to chew or swallow their 180 mg loading dose of ticagrelor before stenting for ST-segment elevation MI (STEMI), favored chewed tablets acutely:

• 30 minutes: 168 versus 230 P2Y12 reaction units (PRU, P=0.003)
• 1 hour: 106 versus 181 PRU (P=0.005)
• 4 hours: 43 versus 51 PRU (P=0.30)

Platelet reactivity in the chewing group was reduced by 24% as early as 30 minutes after taking ticagrelor (P=0.001), according to researchers led by Elad Asher, MD, MHA, of Sheba Medical Center in Israel, online in JAMA Cardiology.

"In patients with STEMI and particularly in patients undergoing primary PCI, the delayed onset of action to oral P2Y12 receptor inhibitors can last for several hours and cause an increased risk of thrombotic complications during and after primary PCI. Results of our trial suggest that chewing ticagrelor offers either a faster absorption via the mucosa and/or a faster absorption in the stomach," they concluded.

"Chewing ticagrelor could overcome the disadvantages of drug absorption via the gastrointestinal tract particularly during the first crucial hours of STEMI."

The FDA approved a crushed route of administration for ticagrelor, a P2Y12 inhibitor not requiring metabolic activation, in 2015. The taste isn't , according to studies by drugmaker AstraZeneca.

The trial by Asher's group used the VerifyNow assay to assess PRU. Patients shared similar baseline characteristics, PRU, and door-to-balloon times between groups.

Relative inhibition of platelet aggregation at 1 hour, the investigators reported, reached 51% in the chewing group and 10% in the standard swallowing group (P=0.005). By 4 hours, the rates were 81% and 76% (P=0.24).

There was one major adverse event reported in each group: one case of cardiogenic shock after PCI in the chewing group and one recurrent acute coronary syndrome in the swallowing group.

Asher and colleagues acknowledged that their single-center study had a small sample size. In addition, platelet reactivity is only a surrogate for ischemic outcomes.

"Larger studies are warranted to investigate if our pharmacodynamics findings translate into improved clinical outcomes in patients with STEMI," they suggested.

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