Participating in the trial will not cost you anything and all study participants will be reimbursed for all travel related to the FUSION study.

During the FUSION study, your health is our number one priority. All medical guidelines are to be followed in study clinics, including the use of gloves, properly prepping needles, and disposing of all materials. Masks, safety goggles, or face shields may also be used for added protection.

If you are eligible and agree to participate in the FUSION study, you will either receive the investigational antisense medicine or placebo during the first part of the treatment period. A placebo is a substance that looks like and is taken the same way as the real potential treatment, but has no active ingredients or medical benefit. Everyone will receive the investigational antisense medicine in Part 2 of the FUSION study.

In clinical trials, a placebo is given to some participants so that the two groups-for FUSION, it is those taking the investigational antisense medicine vs. those taking the placebo-can be compared to show whether the potential treatment being studied is safe and is effective. A placebo can also help researchers determine whether certain changes during the FUSION study happen by chance or actually in response to the treatment.

The screening period will help determine your eligibility to participate, make general and disease-specific health assessments, and provide baseline testing results to compare with the end of treatment. You will also have physical examinations and laboratory tests, if needed, to make sure you are healthy enough and ready to participate. These include, but are not limited to, an ECG, an MRI, and a genetic test to confirm a mutation of the FUS gene.

Because this is a research study, if, after you have completed some or all of the examinations required during the screening period, you may or may not be eligible to participate in the FUSION study.

The total amount of time of the FUSION study is approximately three years (152 weeks) and is being conducted in two parts. The first part is placebo controlled and consists of 8 clinic visits once every 4 weeks, for a total of 7 months. One month after the last visit, a follow up assess­ment takes place. After the assessment, participants have the option to enroll in the second part of the FUSION study. Those who do not enroll in Part 2 will be in a follow-up period for a total of 40 weeks. In Part 2 of the FUSION study, all participants receive the investigation anti­sense drug for an additional 18 months. Participants are assigned to two different groups with one group, dosing every 4 weeks; the second group, dosing every 4 weeks for the first 3 months, then dosing every 8 weeks for the remainder of the treatment period. After the 18-month dosing period is completed, there is a 10 month follow-up period.

Antisense treatments target the production of the disease-causing protein, attacking the root cause of a disease.

This Phase 3 study will evaluate the efficacy of ION363 on clinical function and survival in carriers of fused in sarcoma mutations with amyo­trophic lateral sclerosis (FUS-ALS). ION363 is based on antisense technology, which is a therapy for reducing disease-causing proteins before they are created. The investigational antisense medicine (called ION363) is designed to target and stop the FUS gene from making its protein, which builds up in motor neurons and may contribute to symptoms of ALS. The investigational antisense medicine is administered by an intra­thecal injection (an injection into the fluid surrounding your spinal cord).

FUSION is a clinical study of an investigational antisense medicine for treating Amyotrophic Lateral Sclerosis with Fused in Sarcoma mutations (FUS-ALS). The study will help determine the safety and effectiveness of the potential new treatment using the investigational antisense medicine ION363 for FUS-ALS, which is designed to target and stop the FUS gene from making its protein, which may improve symptoms of ALS.

FUS-ALS is a rare neurological disorder caused by a mutation in the FUS gene that targets nerve cells in the brain and spinal cord. This type of ALS often progresses more rapidly and symptoms can appear at an earlier age. ALS patients may have trouble with certain muscle movements like speaking, walking, or gripping things. As ALS progresses, patients lose muscle control and eventually have life-threatening respiratory com­plications.