ALS Tracker

← All drugs

In development

Tazbentetol

Also known as SPG302

Bottom line

One small study found it well tolerated. Claims of slower decline compare treated people with old trial records, not a placebo group, and are unpublished. The planned 430-person trial is the first real test.

Tazbentetol (formerly SPG302) is a once-a-day pill from Spinogenix designed to help nerve cells rebuild the connections (synapses) they lose in ALS. A small Australian study of 23 people found it was well tolerated. The company reports slower decline than in old patient records, but the placebo period lasted only 28 days, so that claim has no proper comparison group and is not yet in a peer-reviewed journal. A placebo-controlled Phase 2b/3 trial of about 430 people is registered but had not started recruiting by early November 2026.

Information checked 5 Nov 2026

Evidence: Hints only

Studies: 1 mixed · 1 running

Controlled trials missed their main goal. Some measures or subgroups looked better, which needs confirming.

How we decide the overall verdict: How to read this site.

At a glance

CompanySpinogenixExplanation and sources

Spinogenix is a private company in Los Angeles. Tazbentetol is its lead drug and it is also testing it in Alzheimer's disease and schizophrenia, so many of its press releases are about those diseases. It issues frequent news releases about the drug.

Sources

  1. Spinogenix press releasesSpinogenix · Company website
  2. Spinogenix Receives U.S. FDA Fast Track Designation for Tazbentetol for the Treatment of ALSSpinogenix · 5 May 2026 · Company press release
How it worksAims to regrow lost connections between nerve cellsGlutamatergic synapse formationExplanation and sources

In ALS, nerve cells lose their synapses, the contact points that pass signals to other nerve cells and on to muscles. Tazbentetol is designed to make nerve cells grow new excitatory (glutamatergic) synapses. This is a new approach, and it has not yet been proven to work in people.

Sources

  1. Spinogenix Presents Topline Phase 2a Clinical Trial Results for SPG302, a First-in-Class ALS TreatmentSpinogenix · 4 Nov 2025 · Company press release
  2. Spinogenix Receives U.S. FDA Fast Track Designation for Tazbentetol for the Treatment of ALSSpinogenix · 5 May 2026 · Company press release
StagePhase 2Phase 2a done; Phase 2b/3 registered but not yet recruitingExplanation and sources

The Phase 2a study in Australia is complete. The FDA granted Fast Track status in May 2026. The Phase 2b/3 trial (about 430 people, 36 weeks of drug or placebo) was first registered in January 2026 with a start date of March 2026; in September 2026 the start date was moved to October 2026. The registry still showed it as not yet recruiting, with no sites listed, as of early November 2026.

Sources

  1. Spinogenix Presents Topline Phase 2a Clinical Trial Results for SPG302, a First-in-Class ALS TreatmentSpinogenix · 4 Nov 2025 · Company press release
  2. Spinogenix Receives U.S. FDA Fast Track Designation for Tazbentetol for the Treatment of ALSSpinogenix · 5 May 2026 · Company press release
  3. Efficacy and Safety of Tazbentetol in ALS Participants (NCT07325591)ClinicalTrials.gov · Trial registry
  4. Tazbentetol Phase 2/3 registry change history (NCT07325591)DataLookout · News
  5. Tazbentetol (SPG302) Phase 2b/3 ALS study (NCT07325591)Alongside ALS · Patient organisation
Best reported effectUnproven; slower decline vs old records onlyALSFRS-R slope over 6 months vs PRO-ACT recordsExplanation and sources

The Phase 2a study's main goal was safety. It gave 23 people drug or placebo (18 and 5) for only 28 days, too short to compare decline, then everyone took 300 mg a day for another 140 days. The company reports that 82% had a stable or better rate of decline, and that on average they declined 76% more slowly than matched patients in an old database of trial records (PRO-ACT). People who join a new trial often differ from past patients, so such comparisons can make a drug look better than it is. Results are from a company poster and press release, not a peer-reviewed journal.

This is the most favourable result reported. See all key studies for the full picture.

Sources

  1. Spinogenix Presents Topline Phase 2a Clinical Trial Results for SPG302, a First-in-Class ALS TreatmentSpinogenix · 4 Nov 2025 · Company press release
  2. SPG302 Phase 2a ALS poster, NEALS 2025Spinogenix · Conference presentation
  3. Preliminary Phase 2 Data Support Therapeutic Development of Synaptic Regenerative Drug SPG302 in ALSNeurologyLive · News
Who it's forAdults 18 to 80 with ALSAll ALS · Pill, once dailyExplanation and sources

The Phase 2b/3 trial plans to enrol adults aged 18 to 80 with ALS who are on stable standard treatment, are within a set range on the TRICALS risk score, and do not use breathing support.

Sources

  1. Efficacy and Safety of Tazbentetol in ALS Participants (NCT07325591)ClinicalTrials.gov · Trial registry
  2. Tazbentetol (SPG302) Phase 2b/3 ALS study (NCT07325591)Alongside ALS · Patient organisation
What's nextStart of Phase 2b/3 SPARK trialExpected Q4 2026Explanation and sources

The registry lists an estimated start of 1 October 2026, but the trial was still marked "not yet recruiting" in early November 2026, after the start date had already been pushed back once from March 2026. Spinogenix has not issued a press release about the start.

Sources

  1. Efficacy and Safety of Tazbentetol in ALS Participants (NCT07325591)ClinicalTrials.gov · Trial registry
  2. Tazbentetol Phase 2/3 registry change history (NCT07325591)DataLookout · News
  3. Tazbentetol (SPG302) Phase 2b/3 ALS study (NCT07325591)Alongside ALS · Patient organisation
Can I join?Expanded access open in the US; Phase 2b/3 not yet recruitingExplanation and sources

Since May 2025 the FDA has allowed an expanded access programme in the US for up to 200 adults with ALS who cannot join a trial. Spinogenix says eligibility criteria apply; ask your ALS clinic or contact the company.

Sources

  1. Spinogenix Announces FDA-Authorized Expanded Access Program for SPG302Spinogenix · 5 May 2025 · Company press release
  2. Spinogenix Receives U.S. FDA Fast Track Designation for Tazbentetol for the Treatment of ALSSpinogenix · 5 May 2026 · Company press release
  3. Tazbentetol (SPG302) Phase 2b/3 ALS study (NCT07325591)Alongside ALS · Patient organisation

Signal: Steady

Signal measures how often, and how reliably, Spinogenix tells the public about this drug. It says nothing about whether the drug works. A quiet company isn't necessarily a bad sign, but regular, on-time updates help patients plan.

Last company update14 Jul 2026 (4 months ago)12 / 40
Company updates in the last 12 months529 / 35
Promises kept1 of 1 on time25 / 25
Signal score66 / 100 · Steady

Announced milestones

70 or more is Active, 45 or more is Steady, 20 or more is Quiet, below 20 is Silent. Full method.

Timeline

11 events, newest first. Company updates are marked; independent news and regulator decisions are shown too.

2026

  1. Trial registryClinicalTrials.gov (via DataLookout)

    Phase 2b/3 start date pushed to October 2026

    The registry entry was updated to move the estimated start from March to October 2026. As of early November it was still listed as not yet recruiting.

  2. Press releaseFrom the companySpinogenix

    Longer-term Alzheimer's data

    Spinogenix reported data on Alzheimer's patients treated for up to 84 weeks. Not an ALS result.

  3. Press releaseFrom the companySpinogenix

    FDA grants Fast Track for ALS

    Fast Track allows more frequent FDA contact and can speed review. The company said it will help plan its next ALS trial.

  4. Press releaseFrom the companySpinogenix

    Early schizophrenia trial data

    Spinogenix presented interim results from its schizophrenia study at a psychiatry congress. Not an ALS result.

  5. Trial registryClinicalTrials.gov

    Phase 2b/3 ALS trial registered

    A randomised, placebo-controlled trial of tazbentetol in ALS was posted on ClinicalTrials.gov, with a planned start in March 2026.

2025

  1. Press releaseFrom the companySpinogenix

    Alzheimer's Phase 2a results

    Spinogenix reported early cognitive improvements in a small Alzheimer's study of the same drug. Not an ALS result.

  2. Press releaseFrom the companySpinogenix

    SPG302 gets official name tazbentetol

    The World Health Organization approved tazbentetol as the international non-proprietary name.

  3. Press releaseFrom the companySpinogenix

    Topline Phase 2a ALS results

    In 23 people, SPG302 was well tolerated; the company reports 82% had stable or better decline and 76% slower decline than historical records. Most of the study had no placebo group.

  4. RegulatoryEuropean Medicines Agency

    EU orphan designation formally granted

    The European Commission orphan designation EU/3/25/3080 for ALS was recorded on the EMA website.

  5. Press releaseFrom the companySpinogenix

    Company announces EU orphan drug designation for ALS

    Spinogenix said the European Medicines Agency backed orphan status for SPG302 in ALS, which brings regulatory and market-exclusivity benefits in Europe.

  6. Press releaseFrom the companySpinogenix

    FDA authorises US expanded access programme

    Spinogenix said up to 200 adults with ALS who cannot join a trial can get SPG302 through an FDA-authorised expanded access programme in the US.

All sources for this page

  1. Spinogenix press releasesSpinogenix · Company website
  2. Spinogenix Announces FDA-Authorized Expanded Access Program for SPG302Spinogenix · 5 May 2025 · Company press release
  3. Spinogenix Presents Topline Phase 2a Clinical Trial Results for SPG302, a First-in-Class ALS TreatmentSpinogenix · 4 Nov 2025 · Company press release
  4. SPG302 Phase 2a ALS poster, NEALS 2025Spinogenix · Conference presentation
  5. Preliminary Phase 2 Data Support Therapeutic Development of Synaptic Regenerative Drug SPG302 in ALSNeurologyLive · News
  6. Spinogenix Receives U.S. FDA Fast Track Designation for Tazbentetol for the Treatment of ALSSpinogenix · 5 May 2026 · Company press release
  7. Efficacy and Safety of Tazbentetol in ALS Participants (NCT07325591)ClinicalTrials.gov · Trial registry
  8. Tazbentetol Phase 2/3 registry change history (NCT07325591)DataLookout · News
  9. Tazbentetol (SPG302) Phase 2b/3 ALS study (NCT07325591)Alongside ALS · Patient organisation