We, the undersigned, respectfully call for immediate action to address the current restrictions limiting access to the Denali therapeutic drug AVLAYAH for patients suffering from this rare and devastating disease.

We would first like to acknowledge and thank those who have taken steps to investigate the clinical trial involving this treatment. These efforts bring hope to families who are desperately seeking options for care.

We also extend our sincere gratitude to Denali Therapeutics for their unwavering commitment and continued support of all those affected by MPS II. Their dedication to advancing innovative therapies offers meaningful hope to patients and families facing this devastating condition.

However, we are deeply concerned by the decision to deny Jason and Justin Leider and the other 30% in our MPS community access to this potentially life-saving therapy. The current eligibility criteria impose an arbitrary age cutoff—restricting access to patients aged 16 years and 364 days or younger.

This limitation is both unreasonable and unjust. MPS II does not discriminate by age, and patients do not suddenly lose their need for treatment upon turning 17. Denying access based solely on age creates a barrier that is not grounded in compassion or medical necessity.

We believe that the role of regulatory agencies is to ensure the safety and efficacy of treatments—not to prevent critically ill patients from accessing care that may improve or save their lives. Decisions that restrict access in this way raise serious ethical concerns, particularly when they may be influenced by non-medical factors.

Therefore, we urgently petition for:

The immediate reconsideration of the current AGE CAP. 

Expanded access to the Denali therapeutic drug for all individuals diagnosed with MPS II, regardless of age

A compassionate and patient-centered approach to treatment eligibility

No individual or family should be forced to endure the denial of a potentially life-saving therapy due to arbitrary limitations.

We stand together in asking for fairness, compassion, and immediate action.