6 May 2026 - CHOSA Oncology AB hereby announces that the Annual Report for 2025 is available for download on CHOSA's website, https://www.chosaoncology.se. The Annual Report is also attached as a PDF to this press release.
For more information please contact:
Peter Buhl Jensen, CEO
+ 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.
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. 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.