Development

Wave Life's RNA editing oligonucleotide restores wild-type M-AAT in early AATD trial

Wave Life Sciences (Nasdaq: WVE), based in Cambridge, Massachusetts, reported updated data from its Phase Ib/IIa WVE-006 RestorAATion-2 trial showing that its GalNAc-RNA editing therapy restored wild-type M-AAT to levels consistent with the heterozygous MZ phenotype in adults with homozygous Pi*ZZ alpha-1 antitrypsin deficiency, with effects maintained under both biweekly and monthly dosing schedules. The data, presented at the American Thoracic Society International Conference, also showed that treated patients retained the capacity for dynamic AAT upregulation during acute phase responses — a feature absent in the approved alpha-1 antitrypsin deficiency treatment landscape.

The RestorAATion-2 trial (NCT06405633) is an ongoing Phase Ib/IIa open-label study evaluating WVE-006 in adults with AATD carrying the homozygous Pi*ZZ mutation, across single and multiple ascending dose cohorts of eight patients each.

WVE-006 is a GalNAc-conjugated, subcutaneously administered A-to-I RNA editing oligonucleotide — described by Wave as an AIMer — designed to correct the single-base RNA mutation responsible for the Pi*ZZ genotype. Rather than silencing the mutant allele or supplementing protein exogenously, the molecule is intended to redirect translation toward wild-type M-AAT while simultaneously reducing the hepatotoxic Z-AAT isoform. This positions Wave Life Sciences AATD program as mechanistically distinct from the only currently approved intervention, which is weekly intravenous plasma-derived augmentation therapy that addresses lung disease only and has no effect on liver pathology.

Key results from the WVE-006 RestorAATion-2 trial

In the 200 mg biweekly multidose cohort, seven doses over 12 weeks produced mean maximum M-AAT levels of 64.4% of total circulating AAT, with total AAT reaching 11.9 µM. That M-AAT fraction sits within the reference range observed in heterozygous Pi*MZ individuals — 57% to 71%, mean 64% — who carry low risk of lung or liver disease. The 400 mg monthly multidose cohort, receiving four doses over the same period, produced M-AAT at 58.7% of total AAT and total AAT of 13.6 µM, indicating that extending the dosing interval to monthly did not substantially diminish the pharmacodynamic response.

Z-AAT reduction followed a dose-dependent pattern. Single doses reduced circulating Z-AAT by 47.3%, 49.7%, and 59.1% at the 200 mg, 400 mg, and 600 mg dose levels respectively. With multiple doses, reductions reached 70.5% in the biweekly cohort and 67.7% in the monthly cohort. Z-AAT accumulation in the liver is the primary driver of progressive hepatic fibrosis in Pi*ZZ individuals, and no approved therapy currently addresses this component of disease.

A separate observation reinforced the functional relevance of the pharmacodynamic signal. Across the trial, three patients mounted elevated AAT responses during acute phase reactions — one following a kidney stone event, producing total AAT of 20.6 µM, and two following mild upper respiratory infections in the 400 mg multidose cohort, with AAT increases of 57.8% and 59.8% above pre-event levels. The correlation between C-reactive protein and AAT elevation across all available data reached r=0.73 (p < 0.001, n=19), suggesting preservation of dynamic acute phase responsiveness. This dynamic upregulation capacity is not replicated by augmentation therapy, which delivers a fixed exogenous protein load irrespective of physiological demand.

Editing durability extended at least three months after the last dose in both multidose cohorts, supporting the feasibility of infrequent subcutaneous dosing as a practical alpha-1 antitrypsin deficiency treatment approach.

On safety, all adverse events were mild to moderate in intensity. No serious adverse events were reported, and there were no clinically meaningful elevations in liver function tests across any cohort to date.

The AllSci BriefSystematic R&D and deal news. Daily.

Competitive positioning and the RNA editing distinction

The current standard of care for AATD lung disease — intravenous augmentation with plasma-derived AAT — requires weekly infusions and does not address liver pathology. There are no approved therapies for AATD-associated liver disease. Several investigational approaches are in development, including gene therapy and RNA interference strategies, but the Wave Life Sciences AATD program occupies a distinct mechanistic position through RNA editing rather than gene silencing or permanent genomic modification.

The GalNAc-RNA editing therapy approach avoids lipid nanoparticle delivery, which has been associated with hepatic inflammation in some gene therapy contexts. Because editing occurs at the RNA rather than DNA level, the approach avoids permanent genomic modification and may offer a differentiated safety profile relative to DNA editing strategies, although comparative clinical significance remains unproven. The reversibility of RNA editing is cited by Wave as a safety differentiator, though the clinical significance of this theoretical advantage has not yet been established in comparative data.

Cross-trial comparisons are limited by differences in patient populations, assay methods, and endpoints, and the RestorAATion-2 data remain early-stage from a small open-label cohort. The MZ-like phenotype benchmark is a pharmacodynamic surrogate, not a validated clinical endpoint, and whether achieving these protein levels translates to reductions in lung function decline or liver fibrosis progression will require longer follow-up and larger studies.

The 600 mg monthly multidose cohort is still enrolling, with data expected in the second half of 2026. That cohort may clarify whether higher monthly dosing can reliably achieve M-AAT fractions at the upper end of the MZ reference range.

Regulatory pathway and next steps

Wave expects to receive US FDA feedback on a potential accelerated approval pathway for WVE-006 by mid-2026. The basis for that pathway, if pursued, would likely rest on M-AAT restoration or Z-AAT reduction as a surrogate endpoint reasonably likely to predict clinical benefit — a framework that the agency has applied in other rare disease settings but has not yet formally established for AATD.

The 600 mg monthly multidose data, expected in H2 2026, will be the next material readout for the program.


This article was generated with AI assistance and reviewed and edited by the AllSci editorial team Explore more at AllSci News: https://allsci.com/news/


Spot something wrong? Report an issue with this article