For the past 40 years! Innovative medicine for motion sickness has made a big move again

On May 15th, Vanda Pharmaceuticals, a US biopharmaceutical company, announced that its Phase III clinical trial of a new drug, Tradipitant, for the treatment of motion sickness (especially seasickness), had yielded positive results.

Tradipitant is a neurokinin-1 (NK1) receptor antagonist developed by Lilly. Vanda obtained the global development rights to Tradipitant through licensing in April 2012.

Currently, Vanda has been developing Tradipitant for indications including atopic dermatitis itch, gastroparesis, novel coronavirus infection, motion sickness, alcohol dependence, social anxiety disorder, and dyspepsia.

This Phase III trial enrolled a total of 316 patients with a history of motion sickness, who were given either 170 mg of Tradipitant, 85 mg of Tradipitant, or a placebo during boat travel.

All participants had a history of seasickness. The primary endpoint of the study was the effect of tradipitant (170 mg) on vomiting. Key secondary endpoints included: (1) the effect of tradipitant (85 mg) on vomiting; (2) the effectiveness of tradipitant in preventing severe nausea and vomiting.

It is reported that motion sickness remains an unresolved medical need. Since the FDA approved scopolamine (a transdermal patch placed behind the ear) in 1979, there has been no new drug approved for the treatment of motion sickness for more than forty years.

Based on data from two Phase III trials, Vanda plans to submit a marketing application to the FDA for Tradipitant for the treatment of motion sickness in the fourth quarter of 2024.

About motion sickness

Motion sickness, also known as travel sickness, sea sickness, air sickness, and a collective term for diseases caused by various factors such as swaying, jolting, spinning, and acceleration.

Public data shows that approximately 30% of the general population suffer from motion sickness under common travel conditions, including sea, air, and land travel. China is one of the countries with the highest incidence of motion sickness in the world, with 80% of people experiencing varying degrees of motion sickness reactions.

Effective preventive measures for motion sickness include selecting positions with minimal motion stimulation for susceptible individuals (for example, positions near the waterline in the middle of a boat, or positions near the wings of an airplane). Efforts should also be made to minimize the difference between visual and vestibular stimulation.

When traveling by car, it is best to sit in the front row, where motion is most noticeable. When on a boat, focusing on the horizon or land is usually better than focusing on the walls of the cabin.

Regardless of the mode of transportation, avoid reading during the journey and avoid sitting facing backward. Reclining or semi-reclining positions that support the head are the most effective postures for preventing symptoms.

Adequate ventilation also helps prevent symptoms of motion sickness. Additionally, during long journeys, it is better to consume small amounts of water and eat mild foods multiple times rather than consuming large quantities of food and water. Furthermore, research has found that biscuits and carbonated beverages, especially ginger ale, are particularly effective for motion sickness.

Motion sickness medication

Motion sickness doesn't have a definitive cure, but choosing effective antiemetic drugs can help alleviate discomfort.

Scopolamine:

Scopolamine can be administered transdermally (1.5 mg) or orally.

Transdermal patches are a good choice for long journeys, with effectiveness lasting up to 72 hours. Apply behind the ear four hours before the expected onset of action. If medication is still needed after 72 hours, remove the old patch and apply a new one behind the other ear.

Oral scopolamine takes effect within 30 minutes. Administer 1 hour before travel (0.4-0.8 mg), then every 8 hours.

Side effects of the medication include dizziness, blurred vision, dry mouth, and increased heart rate. Using transdermal patches can reduce their occurrence.

Antihistamines:

Antihistamines work by antagonizing acetylcholine. Susceptible individuals can take certain over-the-counter medications such as dimenhydrinate (Dramamine), diphenhydramine, cyclizine, or meclizine an hour before travel. Meclizine and dimenhydrinate cause minimal gastrointestinal symptoms.

Dopamine antagonists:

Dopamine antagonists include prochlorperazine and metoclopramide. Adverse reactions include extrapyramidal symptoms and sedation.

Benzodiazepines:

Benzodiazepine drugs (such as diazepam) may be beneficial for treating motion sickness but have significant sedative effects.

Serotonin antagonists:

Serotonin (5-HT3) antagonists, such as ondansetron and granisetron, are highly effective antiemetics, but they have not shown significant effectiveness in preventing motion sickness.

Conclusion

Motion sickness occurs due to inconsistencies in proprioceptive, visual, and vestibular stimuli, or due to excessive stimulus intensity. Typically, using scopolamine or antihistamines for medication prevention is more effective, but if vomiting occurs, serotonin antagonists can alleviate symptoms.

To reduce the onset of motion sickness, it is recommended to adopt positions with minimal motion stimulation during the journey, try to sleep, ensure ventilation, avoid alcohol, unnecessary food, and beverages.