Evrysdi (risdiplam) and Spinraza (nusinersen) are both drugs that are used to treat spinal muscular atrophy (SMA) in adults and children. SMA is a type of motor neuron disease that destroys motor neurons - the muscle-controlling nerve cells.
Evrysdi and Spinraza work by targeting SMN2 (survival of motor neuron 2) and increasing levels of the SMN protein throughout the body, however, they go about it in two slightly different ways. Increasing SMN protein helps to improve muscle and nerve function in people with SMA.
One of the key differences between these drugs is that Evrysdi is taken orally, unlike Spinraza which is given via intrathecal injection. When Evrysdi was approved for use in August 2020 it not only provided an alternative treatment option for people with SMA who were already receiving treatment, but it also provided the first oral and at-home treatment option for people with SMA, which is particularly important for those people who are unable to receive intrathecal injections.
The table below compares Evrysdi and Spinraza across a range of areas.
| Evrysdi (risdiplam) | Spinraza (nusinersen) | |
| Company | Genentech | Biogen |
| Approval date | First approved August 2020 | First approved December 2016 |
| Dosage Form | Powder for oral solution | Injection in a single-dose vial |
| Administration | Self administered via oral syringe, gastrostomy or nasogastric tube. The medication is made up by a pharmacist and can then be given at home following the instructions of a healthcare provider | Intrathecal injection (injection into the subarachnoid space of the spinal cord/the cerebrospinal fluid) |
| Dosing schedule | Given daily |
Four loading doses required:
|
| Indication / usage | Used to treat spinal muscular atrophy (SMA) in pediatric and adult patients | Used to treat spinal muscular atrophy (SMA) in pediatric and adult patients |
| Drug type | Small molecule drug | An antisense oligonucleotide |
| Mechanism of action | Survival of motor neuron 2 (SMN2) splicing modifier. It works by increasing the ability of the SMN2 gene to make more functional SMN protein, which is lacking in people with SMA | Survival of motor neuron 2 (SMN2)-directed antisense oligonucleotide. It works by rebinding at exon 7 so that the SMN protein produced by the SMN2 gene becomes functional |
| Side effects / adverse effects |
The most common adverse reactions in later-onset SMA occurring in 10% of patients include:
Similar reactions were seen in patients with infantile-onset SMA, plus the following also occurred in at least 10% of patients:
|
The most common adverse reactions occurring in at least 20% of patients and at a frequency of at least 5% more than controls who didn’t receive Spinraza include:
|
| Efficacy |
|
|
| Warnings and precautions | Requires baseline tests before each administration because of thrombocytopenia and coagulation abnormalities and renal toxicity | |
| Special patient populations |
May cause fetal harm Avoid in hepatic impairment |
May cause fetal harm |