Data Readout

Protara's THRIVE-3 heads toward H2 2026 readout with no rival IV choline trial

The Phase 2b/3 trial testing IV Choline Chloride against placebo is recruiting toward an interim analysis Protara has guided to since January, with no approved IV choline product and no competing trial in the same mechanism.

By AppliedXLJuly 13, 2026Trial NCT06910943

Executive Summary

Protara Therapeutics is advancing toward an interim look at its lead asset in a disease population with no approved intravenous treatment option, testing whether the drug clears a threshold the company itself set as the bar for maintaining adequate choline status.
The sponsor has held its guided readout window steady across every disclosure since the trial began dosing, a consistency that argues execution risk sits more with the clinical result than with the calendar.
No trial in the competitive field shares this drug's modality and target combination, which means the interim data will land without a same-class precedent to measure against, for better or worse.
A result clearing the trial's prespecified choline threshold would be the first placebo-controlled evidence that an IV formulation can correct a deficiency described as affecting a majority of patients on long-term parenteral support.

The trial and its stake

THRIVE-3 (NCT06910943) is a seamless Phase 2b/3 study evaluating intravenous Choline Chloride in adolescent and adult patients with intestinal failure who depend on long-term parenteral support and cannot get adequate nutrition orally or enterally. Choline deficiency has been described as affecting 78% of patients dependent on parenteral support, and 63% of those with deficiency show some degree of liver dysfunction, according to Protara's own disclosure. No IV choline formulation is currently approved for this population globally, and Jesse Shefferman, Protara's chief executive officer, said the company believes the drug "could ultimately become the first FDA-approved IV choline therapy for patients dependent on PS". NCT06910943+1

Probability of Success

Endpoint Met91%

Completes82%

Clinical Significance20%

Regulatory87%

The design

The trial opened with an 8-week, open-label, dose-confirmation phase in 24 patients to select a dose, followed by a 24-week randomized, double-blind, placebo-controlled phase enrolling roughly 105 additional patients, with an anticipated total enrollment of 129. Its primary endpoint in the placebo-controlled phase is the change from baseline in peak plasma free choline concentration (Cmax) at Week 8 for patients on Choline Chloride versus placebo. Secondary measures track whether patients maintain plasma free choline concentrations at or above 9.5 nmol/mL through Week 24, alongside liver-function markers such as ALP, AST, ALT, and steatosis measured by MRI-PDFF. Patients who complete either phase are eligible to roll into an open-label extension running to Week 64. NCT06910943+1

Timing consistency

Protara has repeated the same H2 2026 window for the interim analysis in four separate disclosures dated January 7, January 12, March 10, and May 13, 2026, with no revision to the start or end date. The trial began dosing on December 10, 2025, moved from Not-yet-recruiting to Recruiting status on October 24, 2025, and carries a registered primary completion date of June 1, 2027, well past the interim window itself. That gap is structural: the interim analysis is a look inside an ongoing trial, not the final registrational readout. Protara+1

Enrollment and stability

Anticipated enrollment moved from 144 to 129 patients on September 9, 2025, a change the operational model treats as inside its routine band and not a signal of distress. Protocol activity beyond that single enrollment revision has been limited to the routine status update to Recruiting, and the trial's amendment frequency reads as stable. NCT06910943

The competitive field

Among trials touching intestinal failure or parenteral support, the closest comparator by modality is a small-molecule chelator, Edetate Sodium, tested by Boston Children's Hospital, but it shares no target with Choline Chloride and does not test the same biochemical replacement question. Other trials in the broader intestinal-failure and short-bowel-syndrome space, including a lipid emulsion (Lipidem), a growth hormone (Somatropin), the GLP-2 receptor agonist Apraglutide, and a mechanical chyme-reinfusion device, work through different mechanisms entirely and sit only in the same indication family, not the same mechanistic class. THRIVE-3 has no direct comparator sharing both its modality and its mechanism in this population, which leaves the interim analysis without a same-class precedent to benchmark against. NCT06910943

This analysis was produced using AI-assisted reporting systems, AppliedXL data, and official public records. These systems undergo editorial review, quality checks, and regular audits by human experts. Errors may still occur, as with any automated system. Always consult the linked primary sources. Read our AI Editorial Policy.