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How Do Companies Avert Further Frustration Among Neurologists Due to Relyvrio’s (Amylyx) Phase 3 Failure and Donanemab’s (Lilly) FDA delay?

Spherix Global Insights captures neurologists’ reactions within 48 hours of these pivotal announcements.

EXTON, PA., March 12, 2024 For neurologists tasked with delivering the distressing diagnosis of Amyotrophic Lateral Sclerosis (ALS) or Alzheimer’s Disease (AD), the upcoming months may prove equally heart-wrenching. They face the daunting responsibility of informing patients and caregivers that not only is there no cure, but also that medications that previously held the hope of mitigating progression may now be inaccessible. This grim reality was underscored by the unfortunate news delivered on Friday, March 8, concerning the treatment of these debilitating conditions. 

ALS strikes adults in the prime of their life, is fatal, and the life expectancy of patients is generally 15 years or less. ALS patients maintain their cognitive functions while their muscle function deteriorates and eventually renders them bed-ridden, unable to swallow, and unable to breathe.  

Amylyx’s Relyvrio (sodium phenylbutyrate and taurursodiol) showed potential of slowing the disease’s progression in Phase 2 trials, prompting ALS advocates to push for early approval. In an unusual decision the FDA conditionally approved Relyvrio based on the Phase 2 results as long as Phase 3 trial outcomes confirmed the results. On Friday, March 8, Amylyx announced that Relyvrio failed its Phase 3 PHOENIX trial. The company said it would “continue to engage with regulatory authorities…to discuss the results from PHOENIX within the next eight weeks and make informed decisions.” 

The battle against AD, which robs adults of their golden years with progressively worsening dementia, faced a setback with the FDA’s decision to postpone the approval of Lilly’s donanemab. While last summer marked a breakthrough with the FDA’s approval of Eisai/Biogen’s anti-amyloid treatment Leqembi (lecanemab), its uptake has been slow, with only about 2,000 patients in the US receiving the treatment as of January 2024. Neurologists and Alzheimer’s advocates eagerly anticipated the expected Q1 approval of Lilly’s donanemab, another anti-amyloid treatment that could be more effective than Leqembi. 

In response to these developments, Spherix Global Insights surveyed 80 specialists in their US neurologist community to learn how they felt about the Relyvrio and donanemab news and to solicit opinions about what manufacturers should do now to keep their trust. 

When prompted, a majority of neurologists were aware of the Relyvrio news within 48 hours. Spherix’s study captures neurologists’ thoughts on whether Relyvrio should remain available to patients – and if so, for which patients. Additionally, neurologists expressed their preferences for specific actions and communications from Amylyx, such as physician letters or press releases.  

Only 40% of neurologists were initially aware of the FDA announcement regarding donanemab for Alzheimer’s Disease (AD) when prompted. They were subsequently questioned about the implications of this news on their prospective utilization of donanemab and their present use of Leqembi. Spherix also assessed the neurologists’ alignment with the FDA’s decision, with slightly over half expressing agreement. Among those who disagreed, many cited the therapy’s efficacy in clinical trials and emphasized the pressing need for a disease-modifying treatment for AD. 

“There is a high demand for the drug [donanemab], and it has already passed phase 3 trials” – Neurologist 

Neurologists also gave feedback on specific communications Lilly can provide about the Phase 3 results and suggested what Lilly’s actions should be based on the news. 

Spherix will continue to monitor neurologist’s viewpoints on these and other breaking news in Neurology. 

Special Topix™ is an independent service that includes access to a report or series of reports based on current events or topics of interest in specialty markets covered by Spherix. 

About Spherix Global Insights 

Spherix Global Insights is a leading provider of market research, business intelligence and advisory services to the global life sciences industry. The company’s unique service offerings are powered by deep therapeutic knowledge, the Spherix Network specialty physician panel, and commercially relevant analyses to enable strategic decision-making by our valued customers. 

A trusted advisor and industry thought leader, Spherix Global Insights provides specialized market expertise in six (6) focused therapeutic areas including: dermatology, gastroenterology, nephrology, neurology, rheumatology, and ophthalmology. 

To learn more about Spherix Global Insights, visit or connect through LinkedIn. 

For more details on Spherix’s primary market research reports and interactive dashboard offerings, visit or register here: 

For more details on Spherix’s primary market research reports and interactive dashboard offerings, visit or register here:

Read Amylyx Pharmaceuticals’ Press Release here

Read Eli Lilly’s Press Release here

Spherix Global Insights Contacts 

Blaine Cloud, Ph.D., Neurology Franchise Head 

Alissa Algarin, MBA, Insights Director, Neurology 

NOTICE: All company, brand or product names in this press release are trademarks of their respective holders. The findings and opinions expressed within are based on Spherix Global Insight’s analysis and do not imply a relationship with or endorse. 

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