What is Azstarys?
Azstarys is an FDA-approved, once-daily oral stimulant medication containing a fixed combination of serdexmethylphenidate (a prodrug) and dexmethylphenidate (the active methylphenidate) for treating ADHD in patients aged 6 years and older. 1, 2
Formulation and Mechanism
Azstarys contains a unique 70:30 molar ratio of serdexmethylphenidate to dexmethylphenidate in each capsule 1, 2. The serdexmethylphenidate component is a prodrug that gets converted to dexmethylphenidate in the body, providing extended drug release, while the immediate-release dexmethylphenidate component provides rapid symptom control 3.
Available strengths:
- 26.1/5.2 mg (equivalent to 20 mg dexmethylphenidate)
- 39.2/7.8 mg (equivalent to 30 mg dexmethylphenidate)
- 52.3/10.4 mg (equivalent to 40 mg dexmethylphenidate) 1, 2
The prodrug design serves two key purposes: it extends the duration of action throughout the day and potentially reduces abuse liability since the prodrug must be metabolized to become active, making parenteral abuse less rewarding 4, 3.
Clinical Context and Guidelines
Stimulants like methylphenidate are first-line pharmacotherapy for ADHD in children and adolescents aged 6 years and older 5, 6. For elementary and middle school-aged children (6-12 years), FDA-approved medications including methylphenidate formulations should be prescribed as first-line treatment 6. Long-acting formulations like Azstarys are associated with better medication adherence and likely lower risk of rebound effects compared to short-acting stimulants 5.
Efficacy Evidence
In a pivotal laboratory classroom study of children aged 6-12 years with ADHD, Azstarys demonstrated significant improvement in ADHD symptoms compared to placebo, with a treatment effect lasting from 0.5 to 13 hours post-dose 7. The mean improvement on the SKAMP-Combined scale was -5.41 points (p < 0.001), indicating robust symptom control throughout the school day 7.
During dose optimization, high responder rates were achieved: 72-81% of children reached ≥50% improvement in ADHD-RS-5 scores at their optimized dose level 8. A 12-month open-label safety study confirmed sustained efficacy with continued ADHD symptom reduction throughout the treatment period 9.
Safety Profile
Common adverse events include decreased appetite (18.5%), upper respiratory tract infection (9.7%), nasopharyngitis (8.0%), decreased weight (7.6%), and irritability (6.7%) 9. These are consistent with other methylphenidate products.
Important tolerability advantage: Real-world data suggests patients taking Azstarys report lower frequency of insomnia compared to amphetamine ER and lisdexamfetamine, and lower frequency of end-of-dose crash compared to amphetamine ER 10. This may represent a clinically meaningful benefit for patients who struggle with these specific side effects on other stimulants.
No serious adverse events were attributed to treatment in the 12-month safety study, and there were no clinically meaningful trends in cardiovascular parameters 9. The safety profile is comparable to other methylphenidate products with no unexpected findings 9.
Practical Considerations
The capsules can be opened and sprinkled on food, making this an excellent option for children or adults who cannot swallow pills 3. This is a significant practical advantage over some other long-acting formulations.
Dosing typically starts at 39.2/7.8 mg with weekly titration up to 52.3/10.4 mg or down to 26.1/5.2 mg based on response and tolerability 7, 8.
The prodrug formulation provides both rapid onset (within 30 minutes) and extended duration (up to 13 hours), addressing the full school or work day with a single morning dose 7, 3.