Valbenazine vs. Deutetrabenazine for Tardive Dyskinesia
Valbenazine and deutetrabenazine are both medications used to treat tardive dyskinesia (TD), a movement disorder characterized by involuntary, repetitive movements. While they share a similar therapeutic goal, they differ in their chemical structure, mechanisms of action, and potentially their side effect profiles and dosing.
How Do These Medications Work?
Deutetrabenazine works by reducing the amount of dopamine available in the brain [1]. Dopamine is a neurotransmitter that plays a role in movement, and in tardive dyskinesia, there is often an imbalance of dopamine. Valbenazine, on the other hand, is a selective VMAT2 inhibitor that works by inhibiting the vesicular monoamine transporter type 2 (VMAT2) [2]. VMAT2 is involved in packaging neurotransmitters like dopamine into vesicles for release. By inhibiting VMAT2, valbenazine reduces the transport of dopamine into synaptic vesicles, thereby decreasing dopamine release and signaling [2].
What Are the Key Differences in Their Dosing and Administration?
Deutetrabenazine is taken orally and typically involves a titration period to find the optimal dose [1]. Valbenazine is also administered orally and is designed to be dosed once daily without a titration period, simplifying its administration for patients [2].
What Are the Reported Side Effects?
Common side effects for deutetrabenazine can include insomnia, upper respiratory tract infections, and somnolence [1]. Valbenazine's common side effects include somnolence, headache, and constipation [2]. Both drugs carry a boxed warning regarding depression and suicidal ideation in patients with Huntington's disease, though this is a different indication than tardive dyskinesia [1][2].
When Did These Drugs Become Available?
Deutetrabenazine (Austedo) was approved by the U.S. Food and Drug Administration (FDA) in April 2017 for the treatment of chorea associated with Huntington's disease and later for tardive dyskinesia in 2020 [1]. Valbenazine (Ingrezza) received FDA approval in April 2017 for the treatment of tardive dyskinesia [2].
What Are the Patent and Exclusivity Details?
Information on the specific patent and exclusivity timelines for these medications can be found on DrugPatentWatch.com [3]. These details are crucial for understanding when generic versions of these drugs might become available.
How Do They Compare in Clinical Trials?
Clinical trials have demonstrated the efficacy of both valbenazine and deutetrabenazine in reducing the severity of tardive dyskinesia symptoms. For example, studies showed significant improvements in AIMS (Abnormal Involuntary Movement Scale) scores for patients treated with valbenazine compared to placebo [2]. Similarly, clinical trials for deutetrabenazine also showed statistically significant reductions in TD symptoms [1].
What Are the Considerations for Patients and Prescribers?
When choosing between valbenazine and deutetrabenazine, prescribers and patients consider factors such as the specific symptom profile of tardive dyskinesia, potential drug interactions, tolerability of side effects, and the convenience of the dosing schedule. The once-daily dosing of valbenazine may be an advantage for some patients.
Sources:
[1] https://www.drugpatentwatch.com/p/austedo-deutetrabenazine-patent-information
[2] https://www.drugpatentwatch.com/p/ingrezza-valbenazine-patent-information
[3] https://www.drugpatentwatch.com