The first FDA-approved enzyme replacement therapy (ERT) to cross the blood-brain barrier to reach the brain in addition to the body
AVLAYAH is approved for the treatment of neurologic symptoms in pediatric patients weighing at least 5 kg with Hunter syndrome prior to advanced neurologic disease. This approval is based on a reduction of heparan sulfate (HS) in the cerebrospinal fluid (CSF) surrounding the brain and spinal cord. Studies are ongoing to confirm how well it works in improving clinical symptoms.
AVLAYAH is not recommended for use in combination with other enzyme replacement therapies for the treatment of Hunter syndrome.
FDA=US Food and Drug Administration.
Watch the mechanism of action (MOA) video
The Phase 1/2 study was a multi-center, multi-cohort, open-label trial in 47 individuals with MPS II.
Study participant characteristics:
Individuals in the study were followed for a median of 2 years, with some for up to 4 years
Normal was defined as biomarker levels seen in individuals of similar age without MPS II
93%
(41/44) of individuals achieved normalization of CSF HS* by Week 24.
*CSF HS is the primary GAG that accumulates in the brain of individuals with MPS II.
*CSF HS is the primary GAG that accumulates in the brain of individuals with MPS II.
On average, AVLAYAH resulted in 91% reduction of CSF HS levels by Week 24
68%
(26/38) of individuals achieved normalization of uGAG by Week 24.
Clinical results, including CNS and peripheral outcomes, are being assessed in the ongoing Phase 2/3 study
CNS=central nervous system;
CSF HS=cerebrospinal fluid heparan sulfate;
GAG=glycosaminoglycans;
MPS II=mucopolysaccharidosis II;
uGAG=urine glycosaminoglycan.
In 47 patients treated with AVLAYAH:
*Hemoglobin range: 8.0 g/dL to <lower limit of normal.
The most common side effects (≥20%) were IAR, upper respiratory infection, ear infection, fever, anemia, cough, vomiting, diarrhea, rash, COVID-19, runny or congested nose, fall, headache, skin injuries, and hives.

Once enrolled in Denali Patient Services, patients will be connected with a dedicated Denali CARE Partner who will support them with information about coverage, affordability, and logistics. Denali CARE Partners can also provide one-on-one support and check-ins on request, share educational resources, and address patient and caregiver questions about program services and access.
Our Denali CARE Team is here to help with*:

With the Denali Patient Services Copay Program, eligible patients with commercial insurance may pay as little as $0† for AVLAYAH. Please see Program Terms and Conditions for more information, and visit www.avlayah.com/copay to enroll.
Denali CARE Partners can provide information about independent charitable organizations that may offer financial support.
AVLAYAH launch webinar, presented by Dr. Joseph Muenzer
Please select your role to continue
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It is important that every patient read and understand the full Denali Patient Services Copay Program Terms and Conditions. The summary provided here is not a substitute for reviewing the complete Terms and Conditions in their entirety. By enrolling, patients acknowledge and agree to the Terms and Conditions and the Denali Privacy Policy, available at: https://www.denalitherapeutics.com/privacy-policy/.
Enrollment does not guarantee approval or payment of benefits. Denali reserves the right to rescind, revoke, terminate, or change this offer, eligibility, and these Terms and Conditions at any time without notice.
As further described below, in general:
I. ELIGIBILITY
*Eligibility Criteria: Subject to program limitations and terms and conditions the Denali Patient Services Copay Program is open to patients who have been prescribed AVLAYAH and who have commercial or private insurance that covers AVLAYAH, including state and federal plans commonly referred to as “healthcare exchanges plans.” This program helps eligible patients cover out-of-pocket costs related to AVLAYAH, up to program limits. There is no income requirement to participate in this program. Eligibility is dependent on product indication and patient must have a valid prescription for an FDA approved indication.
Patients under 18 years of age must have a parent, legal guardian, or other legally authorized representative to enroll and accept these Terms and Conditions on the patient’s behalf.
This offer is not valid if the entire cost of your AVLAYAH prescription is eligible to be reimbursed by your commercial plan or other private health or pharmacy benefit programs, or if your insurer or plan prohibits use of manufacturer copay assistance.
This offer is not valid for patients whose coverage for AVLAYAH is paid for in whole or in part by Medicare, Medicaid, or any other federal or state healthcare program. It is not valid for cash-paying patients or where prohibited, taxed, or restricted by law. A patient is considered cash-paying when the patient has no insurance coverage for AVLAYAH or where the patient’s insurance provides little or no meaningful coverage for AVLAYAH. Such patients may be considered ineligible because such coverage does not provide a material level of financial assistance for the cost of a AVLAYAH prescription. This offer is only valid in the United States and Puerto Rico at eligible pharmacies and sites of care.
This offer is not valid in combination with any other coupon, discount, prescription savings card, rebate, free trial, patient assistance program, or any other similar offer, including those from third parties or entities that assist insurers or health plans in managing costs.
II. PROGRAM BENEFITS
Denali may modify the benefit amount, in its sole discretion, to satisfy the out-of-pocket cost sharing requirement, including in circumstances where a plan or plan agent (including, but not limited to, a pharmacy benefit manager (PBM)) conditions waiver of some or all out-of-pocket cost sharing on enrollment in or use of this Program.
Some health plans may implement co-pay accumulator or co-pay maximizer programs. These programs are designed to adjust a patient’s out-of-pocket responsibility based on the availability of manufacturer co-pay assistance. In such cases, the Annual Program Maximum may vary over time to ensure that Program funds are applied for the patient’s benefit. Denali also reserves the right to reduce, modify, or discontinue assistance if the patient is enrolled in, or becomes subject to, a co-pay accumulator, co-pay maximizer, or similar program.
Health plans and pharmacy benefit managers (PBMs) are prohibited from enrolling or assisting in the enrollment of patients in the Denali Patient Services Copay Program. The patient or the patient’s legal representative must personally enroll to be eligible for Program benefits.
If at any time a patient begins receiving coverage for treatment under any federal, state, or government healthcare program (including but not limited to Medicare, Medicaid, TRICARE, Department of Defense, or Veteran Affairs programs), the patient will no longer be able to use the Denali Patient Services Copay Program and you must contact Denali Patient Services at 844-DNLI365 (844-365-4365) to stop your participation in this program.
Patients may not seek reimbursement for the value received from the Denali Patient Services Copay Program from any third-party payers, including a flexible spending account or healthcare savings account. Participating in this program means that you are ensuring you comply with any required disclosure regarding your participation in the Denali Patient Services Copay Program and of your insurance carrier or pharmacy benefit manager. Restrictions may apply. Offer subject to change or discontinuation without notice. This is not health insurance.
III. PROGRAM DETAILS
For all eligible patients the Denali Patient Services Copay Program offers:
Maximum Program Benefit, Benefits May Change, End or Vary Without Notice: The program provides up to a Maximum Program Benefit of support to reduce a patient’s out-of-pocket costs that Denali will provide per patient for each calendar year, which must be applied to the patient’s out-of-pocket costs (copay, deductible, or co-insurance and annual out-of-pocket maximum). Patient Program Benefit amounts are unilaterally determined by Denali in its sole discretion and will not exceed the Maximum Program Benefit.
Please ask your Denali Patient Services Representative to help you understand whether your insurance coverage is likely to result in your reaching the Maximum Program Benefit amount by calling 844-DNLI365 (844-365-4365).
Participating patients are solely responsible for updating Denali with changes to their insurance including, but not limited to, initiation of insurance provided by the government, the addition of any coverage terms that do not apply Denali Patient Services Copay Program benefits to reduce a patient’s out-of-pocket costs, such as accumulator adjustment benefit design or a copay maximization program. Participating patients are responsible for providing Denali with accurate information necessary to determine program eligibility. By accepting payments from Denali made on behalf of participating patients, Plans likewise are responsible for providing Denali with accurate information regarding patient eligibility.
By enrolling, patients also agree to: (a) notify the Program immediately if their insurance coverage changes, including enrollment in a government healthcare program or other plan design that may affect Denali Patient Services Copay Program benefits; (b) comply with all requirements of their health plan; and (c) not submit any claim for reimbursement of amounts covered by this Program to any third-party payer, whether public or private, including a Flexible Spending Account (FSA) or Health Savings Account (HSA).
Patients may use the Denali Patient Services Copay Program every time they receive dose of AVLAYAH, up to the Maximum Program Benefit. Benefits reset each calendar year.
IV. ADDITIONAL TERMS
Non-Transferable: The Program benefit is offered to, and intended for, the sole benefit of eligible patients. The Program is limited to one per patient and is not transferable. The Program may not be sold, purchased, traded, assigned, or otherwise transferred. No substitutions are permitted; the Program is valid only for the product indicated.
No Cash Value: This offer is not health insurance, has no cash value, and may not be redeemed for cash. Assistance provided under the Program may not exceed the patient’s out-of-pocket cost for AVLAYAH or the Maximum Program Benefit, whichever is less.
Misuse: Denali may deny or discontinue Program benefits if it determines a patient is ineligible or if it suspects fraud, misuse, or other violation of these Terms and Conditions.
57%
86%
91%