Bolt Completes Prana Merger, Puts PRA-216 at the Forefront of Its Pipeline
Key Facts
Bolt Biotherapeutics completed its merger with Prana Therapies on October 23, 2026, in a stock-for-stock deal, according to a company filing with the U.S. Securities and Exchange Commission. The agreement redirects Bolt’s focus toward developing Prana’s programs, placing PRA-216 at the forefront of its clinical pipeline. The program targets multiple inflammatory pathways and is being developed to treat asthma, chronic obstructive pulmonary disease and atopic dermatitis. The company also plans to study its use in eosinophilic esophagitis. Prana’s programs are thus moving to the center of the combined company’s strategy, as markets await clinical results expected over the coming year.
As consideration, Bolt issued former Prana shareholders 430,746 common shares and 16,360.929 convertible Series D preferred shares. The figures show that the deal was based on shares, with a non-voting, convertible preferred class included in the consideration structure. Before financing, former Bolt shareholders were expected to own about 11.8% of the post-merger common shares, compared with 88.2% for former Prana shareholders, on a fully diluted basis. Those percentages, however, were tied to the pre-financing stage and do not reflect the expected allocation after new investors come in and the preferred shares convert. Comparing the two estimates highlights the expected scale of the change in the ownership base as financing and conversion are completed.
After financing and the full conversion of the preferred shares, Bolt expects former Bolt shareholders to hold 6.9% of the common shares, while former Prana shareholders would hold 51.7%. Private placement investors are estimated to own about 41.4% on a fully diluted basis. That would leave former Prana shareholders as the largest block under the company’s stated estimate, while new investors would hold a substantial stake. Bolt also indicated that investors could own 41.4% after financing and full conversion, consistent with the overall ownership estimate. These figures remain estimates contingent on completion of the financing and conversion of the preferred shares.
The company aims to build its development pipeline around PRA-216, a bispecific antibody targeting IL-4Rα and TSLP. The compound is in Phase 2 development across four treatment areas, including asthma, chronic obstructive pulmonary disease and atopic dermatitis, alongside the planned study in eosinophilic esophagitis. Bolt said Phase 1 data in healthy volunteers showed good tolerability and pharmacodynamic activity across inflammatory markers. It added that the exposure profile supports the potential for at-home maintenance dosing every 8 to 12 weeks. This potential schedule provides an indication of the interval between doses, while the anticipated clinical data from the Phase 2 trials remain the program’s next milestone.
Bolt expects patient data from all four PRA-216 trials to begin coming in the second quarter of 2027 and continue through the fourth quarter of the same year. The timeline represents a series of disclosures across several trials, rather than a single readout expected on one date. The company is also planning its second program, a bispecific antibody that includes IL-31, with first-in-human studies in healthy volunteers and patients expected to begin in the second half of 2027. Bolt expects clinical data for that program during the same half of the year. The company’s announced clinical milestones therefore extend from PRA-216 results throughout 2027 to the second program entering human testing in the second half of the year.
On the management front, Bolt appointed Sheila Gujrathi, Prana’s co-founder and former chief executive, as chief strategy officer; she also joined Bolt’s board. The appointment brings former Prana leadership into a strategic role at the company now developing its programs. Regarding the deal process, Bolt said the merger itself did not require approval from its shareholders, while conversion of the preferred shares does. The company had expected to complete the private financing on October 26, 2026, subject to customary closing conditions. BOLT shares closed at $6.59 on October 30, according to EL7 data.