Disease-Modifying Pharmacotherapy: Riluzole and Emerging Therapeutics

Although there is currently no cure for ALS, disease-modifying therapies aim to slow functional decline and extend survival. Riluzole remains the clinical benchmark for disease-modifying pharmacotherapy.

Riluzole: Evidence and Clinical Guidelines

Despite numerous Phase II and Phase III clinical trials evaluating diverse agents, Riluzole remains the established disease-modifying drug supported by Cochrane systematic reviews.

                     RILUZOLE CLINICAL SPECIFICATIONS
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│ • Standard Dosage  : 100 mg daily (50 mg orally twice daily)           │
│ • Primary Mechanism: Glutamate release inhibition & anti-excitotoxicity│
│ • Clinical Benefit : Prolongs median survival by 2 to 3 months        │
│ • Target Patient   : Probable/Definite ALS, symptoms < 5 yrs,          │
│                      FVC > 60%, age < 75 years                        │
│ • Adverse Effects  : Nausea, asthenia, altered LFTs (requires monitoring)│
└─────────────────────────────────────────────────────────────────────────┘

Evaluation of Investigational Therapeutics

Multiple neuroprotective, anti-inflammatory, and antioxidant compounds have undergone clinical trial evaluation:

Drug Agent	Proposed Mechanism	Target Dosage / Route	Clinical Outcome / Trial Status
Riluzole	Glutamate release inhibitor	100 mg/day oral	Modestly effective; prolongs survival by 2–3 months.
Gabapentin	Anti-excitotoxic agent	3600 mg/day oral	No evidence of beneficial effect on survival/progression.
Lamotrigine	Glutamate release inhibitor	300 mg/day oral	No evidence of clinical efficacy.
Topiramate	Anti-excitotoxic agent	Up to 800 mg/day oral	Did not alter decline; higher doses not warranted.
BDNF / CNTF	Neurotrophic factors	Intrathecal / Subcutaneous	Failed primary efficacy endpoints; toxicity at higher doses.
Creatine	Mitochondrial stabilization	10 g/day oral	No beneficial effect on survival or disease progression.
Vitamin E	Antioxidant	500 mg twice daily oral	No significant effect on survival or motor function.
Pentoxifylline	TNF-alpha inhibitor	1–2 g/day oral	Not beneficial; should be avoided with Riluzole.

Key Takeaways

• Riluzole (100 mg/day) prolongs median survival by 2 to 3 months.

• Regular liver function test (LFT) monitoring is required due to potential hepatotoxicity.

• Many historical neuroprotective candidates (e.g., Creatine, Gabapentin, BDNF) failed to demonstrate clinical efficacy.