Antihistamines: safety of bilastine in a high-speed test with allergic patients

Antihistamine Bilastine:

Anti-allergic agents work by stopping histamine, a substance produced by the patient's own body, which is why they are called antihistamines. One of these is bilastine, which is a highly selective, non-sedating (i.e., "sedating") agent used for symptomatic allergic conditions such as allergic rhinoconjunctivitis and urticaria. Available data suggest that the agent does not impair driving ability or flight performance, although values of driving ability under extreme conditions are not available. Older antihistamines in particular can cause drowsiness as a side effect, which in turn could also affect driving ability.

In the study published in 2018, the effect of bilastine was analyzed on psychophysical performance during a one-week treatment with 20 mg of the drug in patients with allergic rhinitis or chronic urticaria. This was investigated by means of driving tests in a high-speed Formula 1 simulator.

High-speed study:

Published in the scientific journal European Review for Medical and Pharmacological Sciences, the Phase 4, monocentric, single-arm, open-label study included a total of 19 outpatients with allergic rhinitis or chronic urticaria. These were able to perform a driving test on an F1 high-speed simulator.

Significant inclusion criteria included:

• Age between 21 and 55 years
• BMI between 19 and 30
• Ability to give informed consent
• Negative pregnancy test or contraception min. 30 days prior to study entry and during study duration
• Current driver's license for more than 3 years
• At least 5000 km of driving per year.

After study participants were screened and underwent initial familiarization for the driving test, a first trial of the driving test was scheduled at the end of placebo treatment before bilastin treatment and another trial after bilastin treatment.

The primary endpoint was the ability to hold the vehicle in a centered position at speeds of 50 km/h, 150 km/h, and 250 km/h.

The Formula 1 test lasted a total of half an hour and consisted of three tracks.

1. To get used to the test procedure
2. Linear track without obstacles
3. Reaction test of the subjects participating in the study to the stimuli and obstacles.

The varying constant speeds served to better measure the different reaction parameters and difficulty conditions. There was no change of direction in the test - the vehicle had to be steered in either a predetermined straight line or a very wide curve.

The following parameters were evaluated:

• Standard deviation of lateral position - evaluation of attention and ability to follow the given route.
• Maintaining constant speed (30 seconds in each of the different km/h) - evaluation of attentional capacity. The lengths of the distances were adjusted accordingly from 400 m, 1250 m to 2000 m.
• Reaction time - evaluation of reaction capacity and attention level. During the simulation drive, the study participants were asked several times to perform different actions on the steering wheel. These were signaled in the dashboard by illuminated indicators. After the signal lit up, the participant subjects had to press one of two buttons (positioned on the left and right side) while driving. The time difference between the appearance of the signal and the pressing of the button was measured.

Significant results:

No study participant recorded serious adverse effects or incidents. One subject reported bradycardia (i.e., slowed heart rate below 60 beats per minute), which was classified as a treatment-related adverse event. A subsequent medical review revealed that the bradycardia was already present on the ECG at baseline.

According to researchers, bilastine demonstrated an optimal safety profile and was found to be well tolerated in association with adverse events, vital signs and laboratory parameters. Furthermore, the study notes that no adverse effects were recorded under top speed simulation in terms of lane keeping, constant speed, attention and reaction behavior of the study subjects.

Through the analysis, there was even a slight improvement in the ability to steer the vehicle centrally, but this was explained by the fact that the study participant subjects would have slowly become accustomed to the simulation.

According to the study, the results at the top speed of 250 km/h were similar to those at the lowest speed of 50 km/h as well as the average speed of 150 km/h.

Conclusion:

According to researchers, the study showed that the drug bilastine in the dose of 20 mg (in the period of 7 days) did not record any negative effects on the reaction and attention of allergy patients with allergic rhinoconjunctivitis or urticaria, during a maximum speed simulation of up to 250 km/h. The researchers compared this to other observations in which bilastine would not have recorded drowsiness symptoms at the same dose/single dose.