Kronos Bio Stock Price, News & Analysis

Kronos Bio, Inc. (former Nasdaq: KRON) is a biopharmaceutical company that has focused on the discovery and development of small molecule therapeutics that address deregulated transcription, a hallmark of cancer and autoimmune diseases. According to company disclosures, Kronos Bio has described itself as a clinical-stage organization dedicated to developing small molecule therapeutics for cancers and other diseases driven by deregulated transcription.

The company reports that its work centers on a proprietary discovery engine that decodes complex transcription factor regulatory networks to identify druggable cofactors. Kronos Bio states that it screens for and optimizes small molecules that target these cofactors in a disease- or tumor-specific context. This approach has supported a pipeline that, based on company communications, has included drug candidates in oncology and autoimmune disease.

Business focus and discovery engine

Kronos Bio has characterized deregulated transcription as a core biological feature of many cancers and autoimmune conditions. Its proprietary discovery engine is described as decoding transcription factor regulatory networks and identifying cofactors that can be modulated with small molecules. The company has indicated that this platform has enabled the development of p300 lysine acetyltransferase (KAT) inhibitor programs and other small molecule candidates.

In public materials, Kronos Bio has highlighted a focus on transcription factors such as interferon regulatory factor 4 (IRF4) and cofactors such as p300, describing how these proteins influence tumor cell growth, survival, and inflammatory pathways. By targeting these cofactors, Kronos Bio aims to modulate disease-relevant transcriptional programs.

Therapeutic areas and pipeline themes

Company announcements describe Kronos Bio as developing small molecule therapeutics for cancers and autoimmune diseases driven by deregulated transcription. Kronos Bio has reported work on a pipeline that has included:

• Oncology programs focused on cancers where deregulated transcription and specific transcription factor–cofactor relationships are implicated, including multiple myeloma and human papillomavirus (HPV)-driven tumors.
• Autoimmune disease programs where p300 KAT inhibition is being explored as an approach to modulate multiple pro-inflammatory signaling pathways and reduce inflammation.

According to the company, its p300 KAT inhibitor programs are designed to exploit dependencies in cancer cells and immune cells on transcriptional cofactors, with the goal of restoring tumor suppressor activity in cancer or reducing inflammation in autoimmune disease.

Research locations and organizational footprint

Kronos Bio has stated that it is based in San Mateo, California, with a research facility in Cambridge, Massachusetts. In later regulatory filings, the company’s principal executive offices are listed in San Diego, California. These disclosures indicate that Kronos Bio’s operations have included multiple locations in the United States associated with corporate and research activities.

Corporate transformation and acquisition by Concentra Biosciences

Kronos Bio has undergone a significant corporate transformation. On May 1, 2025, the company announced that it had entered into a definitive merger agreement with Concentra Biosciences, LLC. Under this agreement, a wholly owned subsidiary of Concentra commenced a tender offer to acquire all outstanding shares of Kronos Bio common stock for a cash payment per share plus a non-tradeable contingent value right, with potential additional payments tied to dispositions of specified product candidates and cost savings, as described in the merger-related disclosure.

According to a Form 8-K filed on June 20, 2025, the tender offer was completed and Merger Sub merged with and into Kronos Bio on June 20, 2025, with Kronos Bio continuing as the surviving corporation and becoming a wholly owned subsidiary of Concentra. The filing states that, as a result of the consummation of the offer and the merger, there was a change in control of the company.

Delisting and termination of SEC registration

Following completion of the merger, Kronos Bio’s common stock ceased trading on The Nasdaq Global Select Market. The June 20, 2025 Form 8-K reports that the company notified Nasdaq of the consummation of the merger and requested that Nasdaq suspend trading of the shares and file a Form 25 to effect the delisting of the common stock from Nasdaq and deregistration under Section 12(b) of the Securities Exchange Act of 1934.

A Form 25 filed by Nasdaq Stock Market LLC on June 20, 2025, identifies Kronos Bio, Inc. and its common stock as the class of securities removed from listing and/or registration on Nasdaq. Subsequently, a Form 15 filed on June 30, 2025, by Kronos Bio, Inc. certifies the termination of registration under Section 12(g) of the Exchange Act and suspension of reporting obligations under Sections 13 and 15(d) for its common stock. The Form 15 notes that the approximate number of holders of record as of the certification date was one.

These filings indicate that Kronos Bio’s common stock is no longer listed on Nasdaq and that the company has terminated its registration and periodic reporting obligations for that class of securities. For investors, KRON functions as a historical ticker representing the period when Kronos Bio was a publicly traded company prior to its acquisition by Concentra Biosciences.

Strategic alternatives and restructuring activities

In company announcements from late 2024, Kronos Bio reported that it was evaluating strategic alternatives focused on maximizing stockholder value. The company disclosed that these alternatives could include an acquisition, merger, reverse merger, other business combination, sales of assets, or other strategic transactions. As part of these efforts, Kronos Bio announced cost reduction strategies, including a significant workforce reduction, and the discontinuation of development of a CDK9 inhibitor in a specific ovarian cancer setting based on an assessment of benefit-risk profile.

The company also described plans to explore options for its remaining internally developed preclinical assets, including potential partnering of p300 KAT inhibitor programs in oncology and autoimmune disease. These strategic and restructuring activities formed the backdrop for the eventual merger with Concentra Biosciences.

Scientific approach to deregulated transcription

Across multiple scientific and corporate updates, Kronos Bio has emphasized its focus on transcription factor regulatory networks and cofactors. The company reports that its proprietary discovery engine maps these networks to identify relationships, such as those between IRF4 and p300, that may be exploitable with small molecule modulators. In its communications, Kronos Bio has described how p300 KAT inhibition can modulate pro-inflammatory signaling pathways and influence tumor suppressor pathways in preclinical models.

These disclosures position Kronos Bio’s historical business model as centered on applying network-level understanding of transcription to generate small molecule candidates for oncology and autoimmune indications.

KRON as a historical equity symbol

Because Kronos Bio has been acquired and its common stock has been delisted and deregistered, KRON is best understood as a historical equity symbol. The company’s SEC filings and news releases document its evolution from a publicly traded clinical-stage biopharmaceutical company to a wholly owned subsidiary of Concentra Biosciences. For users researching KRON, the focus is on understanding Kronos Bio’s scientific strategy, pipeline themes, and the sequence of corporate events leading to the merger and delisting.