Chosa Oncology AB: CHOSA Oncology accelerates value creation by entering into a commercially driven licensing agreement with Aida Oncology

Under the agreement, CHOSA grants AIDA rights to utilize Platin-DRP® within breast cancer, while AIDA grants CHOSA rights to utilize its taxane (TaxaTect™) drug response predictor within lung cancer.  While platin is a key component of first line therapy of lung cancer taxanes as Taxol and Taxotere are mainstays in 2nd line lung cancer therapy.

The agreement provides both companies with access to complementary technologies that strengthen their respective precision oncology offerings for commercialization.

The agreement builds on successful prediction study presenting joined data at the ASCO Annual Meeting 2026. In the study, it was demonstrated how both predictors worked together to identify an optimal treatment strategy in early breast cancer.  Opening for a commercial utilization of a combined use.

"This partnership represents an efficient way for CHOSA to accelerate value creation. By leveraging the combined technologies, datasets and expertise, CHOSA can expand into new indications faster and with lower development risk. Recognizing the overlap of founders in the two companies, the decision of this agreement was taken by the independent board members of CHOSA.  The non-exclusive structure preserves full flexibility for future licensing, partnership and commercial opportunities for CHOSA," said Ingrid Atteryd Heiman Chairperson of CHOSA Oncology AB.

About the collaboration

The agreement establishes a mutual worldwide non-exclusive licensing framework with full flexibility for future licensing, partnership and commercial opportunities for both companies under which:

· AIDA receives rights to utilize CHOSA's Platin-DRP® technology within breast cancer against an undisclosed fee per test.

· CHOSA receives rights to utilize AIDA's TaxaTect™ technology within lung cancer against an undisclosed fee per test.

· Each company retains ownership of its respective intellectual property.

The agreement has been reviewed by CHOSA's Governance Committee, comprising independent Board members, to ensure that the transaction is conducted on an arm's-length basis.

This information is information that CHOSA Oncology AB is obliged to make public pursuant to the EU Market Abuse Regulation (MAR). The information was submitted for publication, through the agency of the contact person set out above, at 14:40 CET on 27 August.

For more information please contact:

Peter Buhl Jensen, CEO

peter@chosa.bio

+ 45 21 60 89 22

About CHOSA Oncology AB
CHOSA Oncology is a precision oncology company developing Platin-DRP®, a gene expression-based biomarker that predicts response to platinum-based chemotherapy. By identifying patients most likely to benefit, CHOSA aims to improve outcomes and optimize treatment selection in cancer care.

ABOUT AIDA Oncology ApS

AIDA Oncology is a precision oncology company focused on breast cancer. Through its Tect® platform, AIDA develops RNA gene expression-based biomarkers for some of the most widely used cancer drugs, including taxanes, anthracyclines, and now platinum drugs. The pipeline also includes biomarkers for CDK4/6 inhibitors and TOP1 inhibitors used in new ADC therapies.

Background

Cisplatin and its sister molecule carboplatin have been cornerstones in lung cancer therapy for decades. Despite advances in immunotherapy, platinum drugs remain critical in treatment regimens, including combinations with PD-1/L1 inhibitors. While numerous efforts to predict cisplatin efficacy have failed, the Platin-DRP, based on a 205-gene biomarker signature, has shown promising results in other settings, including adjuvant therapy in NSCLC and progression-free survival in breast cancer.

As previously announced, CHOSA is also exploring the predictive potential of Platin-DRP in those treated with carboplatin in lung cancer. Data from the SPLENDOUR trial provides a unique opportunity to validate this tool in a large cohort and potentially confirm its utility across both drugs. Future research will also aim to determine whether Platin-DRP can predict the effectiveness of platinum drugs combined with PD-1/L1 inhibitors. CHOSA Oncology AB is an oncology biotechnology company led by an experienced international team with expertise in oncology, drug development, clinical trials, regulatory affairs, and business development. CHOSA intends to enter into partnership or sublicensing agreements for LiPlaCis® and the DRP®.

About Platin-DRP, a test to predict if cisplatin treatment is likely to be successful

CHOSA is focused on its Platin-DRP® drug response predictor, to which it holds worldwide rights. Platin-DRP is a validated test designed to help identify patients most likely to benefit from cis- and carboplatin treatment. Most recently, CHOSA presented results from the ETOP/EORTC SPLENDOUR study demonstrating that patients with advanced lung cancer predicted to benefit from platinum therapy achieved a median overall survival of 16.9 months compared with 5.6 months for patients predicted not to benefit.

Breast: Strong phase 2b data in metastatic breast cancer have shown that patients selected by DRP® responded better to treatment, had longer progression-free survival, and may also have achieved longer overall survival than patients identified as unlikely to respond well.

Lung: Platin-DRP has also demonstrated its ability to predict the benefit of adjuvant cisplatin in lung cancer. Cisplatin treatment after surgery remains a gold standard that can improve cure rates, but doctors have not had a validated tool to identify which patients are most likely to benefit. This is where Platin-DRP may become a game changer, particularly in newer neoadjuvant settings where immunotherapy has shown high efficacy in combination with platinum doublets. Platin-DRP was validated in a blinded retrospective study in two lung cancer patient cohorts receiving cisplatin after surgery to eliminate residual tumour cells. Patients with the 10% highest scores had a 3-year survival of 90%, whereas patients with the lowest 10% scores had a 3-year survival of only 40%¹. In 2026 CHOSA in collaboration with key opinion leaders in lung cancer showed the Platin-DRP in advanced clearly separated the patient with a sensitive cancer from a platin resistant tumor with a median survival of 16.9 months in the former group vs only 5.5 months in the latter2.  

Immunotherapy Cisplatin and carboplatin have often been shown to activate the immune system, potentially making "cold" tumours more susceptible to PD-1 inhibitors. This synergy may be important not only in lung cancer, but also in breast cancer, bladder cancer and head & neck cancer. In the growing PD-1 inhibitor market, CHOSA's approach may offer the ability to predict whether platin can provide synergy with PD-1 inhibition, potentially creating a meaningful advantage for treatment selection and future partners.

1) Buhl et al PLOS One doi: 10.1371/journal.pone0194609 2) ESMO Open Volume 11, Supplement 3, 106773, April 2026

DRP® is a registered trademark of Allarity Therapeutics, Inc., and is used under license granted to CHOSA. LiPlaCis is in-licensed from Allarity Therapeutics Ltd (previous Oncology Venture ApS) and LiPlasome Pharma ApS.