Kathleen Somera-Molina, Head of SMA Global Medical Affairs at Biogen Shares Insights on New Data Published about SPINRAZA

Shots:

Kathleen spoke about the results of a new study published in Advances in Therapy evaluating real-world adherence to SPINRAZA (nusinersen) with its unique dosing schedule among people with spinal muscular atrophy (SMA)
She also talked about the overall adherence rates to nusinersen. She highlighted that adherence was higher during the maintenance phase than the loading phase in the claims analysis vs. EHR analysis which saw similar adherence in both cases
The interview highlights how Biogen is advancing its research aimed at addressing unmet needs and improving clinical outcomes for individuals impacted by SMA

Smriti: Congratulation on the publication, this is a very informative piece. Can we start giving a key outcome of the published paper?

Kathleen Somera-Molina: A study recently published in Advances in Therapy evaluated real-world adherence to SPINRAZA® (nusinersen) with its unique dosing schedule among people with spinal muscular atrophy (SMA). Results show most SPINRAZA doses were received on time, consistent with the recommended dosing schedule.

The study findings also highlight the importance of careful methodological approaches when using real-world administrative databases for evaluation of treatment patterns with SPINRAZA.

Smriti: Can you provide a brief overview of the study and its objectives?

Kathleen Somera-Molina: SMA is a rare neuromuscular disease characterized by progressive muscular atrophy and weakness. SPINRAZA was the first treatment approved for SMA and has a unique dosing schedule administered through lumbar puncture. The U.S. Food and Drug Administration (FDA)-approved dosing regimen is three loading doses at 14-day intervals, a fourth loading dose 30 days later, and maintenance doses every 4 months thereafter.

Using two large US databases, one based on U.S. electronic health records (EHR) and the other on commercial insurance and Medicaid claims, researchers evaluated real-world adherence to nusinersen with its unique dosing schedule among generalizable populations of patients with SMA.

Smriti: What were the adherence issues which are being addressed with this drug and in this analysis?

Kathleen Somera-Molina: Adherence to medicines in the real world is important for patients with chronic disease to see long-term benefits of treatment. This study shows the importance and challenges of measuring adherence using real-world administrative data sources. This is especially important for drugs given through lumbar puncture with unique dosing schedules, such as SPINRAZA.

Previous studies have produced conflicting data on real-world adherence with SPINRAZA. Retrospective observational studies based on U.S. commercial claims often provide an incomplete picture of all medications received by a patient, which may lead to inaccuracies in calculating patient adherence or treatment-related outcomes in the absence of appropriate study methods. That’s why it is important to use careful methodological approaches for these analyses.

Smriti: What were the primary data sources used in this study, and how were they used to examine adherence to nusinersen in patients with SMA?

Kathleen Somera-Molina: To evaluate real-world adherence to nusinersen, we used de-identified data from two large U.S. databases: the Optum^® EHR database and the Merative™ MarketScan^® Research Databases, which includes commercial insurance and Medicaid claims. Baseline demographics, number of nusinersen administrations on time, and distribution of inter-dose intervals were summarized.

In total, the analysis included 358 SMA patients — 67 patients from the EHR database and 291 from the two claims databases. Of the latter group, 170 patients (58.4%) were in the commercial insurance database, and 121 (41.6%) in the Medicaid database.

To calculate real-world adherence and treatment patterns of nusinersen, the percentage of doses on time was determined using grace periods of 7 days for loading doses and 30 days for maintenance doses, based on U.S. expert clinical opinion and pharmacokinetic modeling. Distribution of intervals between two doses or what we refer to as inter-dose intervals were calculated for the second dose and all subsequent doses for patients who received at least two doses.

Smriti: What were the key findings of the study in terms of overall adherence rates to nusinersen, as well as factors associated with higher or lower adherence rates?

Kathleen Somera-Molina: Of the overall study population, 60 (89.6%) patients from the EHR database and 230 (79%) in the claims database received two or more doses of SPINRAZA during the study period. In both data sources, most SPINRAZA doses were received on time (93.9% EHR, 80.5% claims).

Adherence was higher during the maintenance phase (90.6%) than the loading phase (71.1%) in the claims analysis, in contrast with the EHR analysis which saw similar adherence in the maintenance and loading phases (95.5% and 92.6% of doses received on time, respectively), suggesting that not all loading doses of SPINRAZA may be accurately captured in claims.

The calculated inter-dose intervals aligned with the expected dosing scheduled of SPINRAZA in both data sources.

Smriti: Can you discuss some of the limitations of the study, and how these limitations might affect the generalizability of the findings?

Kathleen Somera-Molina: Despite the rigorous methodology applied to the analyses, there are several limitations to the study, which include:

Some patients my have inaccurate information on the date of SPINRAZA initiation
Reasons for nonadherence such as clinical, logistical, or administrative factors are unknown in both the EHR and claims databases
Analyses were conducted pre-COVID and did not assess the impact of COVID-19 to the adherence of SPINRAZA treatment
Potential overlap of patients in both data sources
Discontinuation of SPINRAZA was not examined due to limitations of real-world administrative databases

Smriti: How might the findings of this study inform clinical practice or healthcare policy around the treatment of SMA with nusinersen?

Kathleen Somera-Molina: Real-world adherence to SPINRAZA is important for long-term treatment effectiveness in SMA. Most SPINRAZA doses were received on time in this real-world analysis, consistent with the recommended schedule. Our findings highlight the importance of careful methodological approaches when using real-world databases in research studies evaluating treatment patterns.

Smriti: Are there any next steps or areas for future research that you think would be particularly important to pursue in light of the study's findings?

Kathleen Somera-Molina: We believe further studies that evaluate real-world adherence with longer follow-up times and larger sample sizes are needed.

Image Source: Canva

About the Author:

Kathleen Somera-Molina is the Global Medical Affairs Head for Spinal Muscular Atrophy (SMA) at Biogen. Prior to joining Biogen, she was at Alexion Pharmaceuticals as the Global Medical Director Lead in a rare blood disorder called paroxysmal nocturnal hemoglobinuria (PNH) and medical monitor for the PNH Registry. Kathleen is trained in Clinical Investigation and Neuroscience from Northwestern University where her scientific research focused on the role of neuroinflammation and glial activation in neurological disorders including stroke, traumatic brain injury, and epilepsy.