By Kelly Cloonan

Cyclerion Therapeutics entered an agreement to integrate Medsteer's anesthetic delivery technology into its lead program, CYC-126, which is in development for treatment-resistant depression. The collaboration aims to accelerate the development of CYC-126 and reduce technical and execution risks, the biopharmaceutical company said. The stock jumped 49% to $2.06 in after-hours trading.

Vistra plans to acquire Cogentrix Energy from Quantum Capital Group in a deal valued at about $4 billion, including cash, equity and debt. The electricity and power-generation company said the acquisition would include 10 natural gas generation facilities totaling about 5,500 megawatts of capacity, helping it meet growing customer demand and diversify its geographic footprint. Shares rose 4.8% to $170.76 in late trading.

Zeta Global disclosed plans to use OpenAI's models to support its artificial intelligence agent for enterprise marketing. Zeta will also have the opportunity for early access to new OpenAI models and features. The company plans to offer the agent to all customers by the end of the first quarter due to strong demand from brands and agencies, it said. The stock gained 8.9% to $23.59 after market close.

Alumis said it plans to share topline data from a Phase 3 trial evaluating envudeucitinib to treat moderate-to-severe plaque psoriasis. The biopharmaceutical company said it will report the data on Tuesday and host a conference call to discuss the results the same day. The stock climbed 16% to $9.64 in after-hours trading.

Write to Kelly Cloonan at kelly.cloonan@wsj.com

(END) Dow Jones Newswires

January 05, 2026 18:43 ET (23:43 GMT)

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