July 01, 2025 – CHOSA announces that the timeline from the collaboration with ETOP on validating the platin-DRP on data from the Splendour study will be pushed into Q3 2025. Late in the biopsy gathering process we have been given the option to look at additional study biopsies. A positive opportunity for CHOSA that we have decided to accept. This will result in c. 110 biopsies living up to CHOSA’s quality criteria.

The expected release timeline for results from this blinded, retrospective study using CHOSA’s Platin Drug Response Predictor (Platin-DRP®) to assess cisplatin efficacy in lung cancer is now to Q3 2025. The study, based on patients from the SPLENDOUR trial treated with platinum-based chemotherapy, aims to distinguish responders from non-responders. Next step will be to test the Platin-DRP® in patients treated with the combination of platin and immunotherapy (PD(L)-1) drugs.

Cisplatin and carboplatin are widely used in lung cancer treatment, benefiting a significant portion of patients. As some of the most effective and commonly used chemotherapy agents, understanding which patients will respond to cisplatin and carboplatin is crucial for optimizing treatment strategies and improving patient outcomes. Conducted in collaboration with leading international lung cancer experts, this study leverages clinical data already gathered from a large-scale trial to predict which patients benefit from cisplatin treatment and which do not and is consequently a very cost-effective way to run clinical trials.

CHOSA will apply its proprietary algorithm, based on a 205-gene test, to predict cisplatin and carboplatin treatment outcomes for patients from the SPLENDOUR trial. The trial included more than 500 patients and tissue that fulfils CHOSA’s quality criteria is available from c. 110 patients. CHOSA's study will provide the following key insights:

1. Cisplatin Prediction Data: This will contribute to the validation of CHOSA’s algorithm following its validation in a late-stage, prospective breast cancer trial and two previous lung cancer studies using cisplatin as adjuvant therapy.
2. Carboplatin Prediction Data: This will represent the first prediction data on carboplatin in lung cancer using the Platin-DRP.
3. Testing NanoString Technology: CHOSA will also evaluate a novel technical prediction method, NanoString, expanding its capabilities and providing an additional platform for future commercialization.

Cisplatin and its sister molecule carboplatin are used in 16 different cancer indications and have been cornerstones in lung cancer chemotherapy for decades. Complementing the progress seen in immunotherapy platinum drugs continue to play a vital role in treatment regimens, including combinations with PD-1/PD-L1 inhibitors such as Keytruda and Opdivo.

The DRP tool is expected to play a critical role in the continued success of PD-1 and PD-L1 therapies. With the PD-1/PD-L1 market currently valued at $60 billion per year, CHOSA’s innovation could be pivotal in advancing the personalization of next-generation immuno-oncology.

A patent application expands CHOSA’s global rights from platinum efficacy prediction to also include platinum - immunotherapy combinations - addressing a major unmet need in oncology was recently applied for.

For additional information, contact:
Peter Buhl Jensen, CEO
Peter@chosa.bio  
+ 45 21 60 89 22

Background

Cisplatin and its sister molecule carboplatin have been cornerstones in lung cancer chemotherapy 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 Cisplatin-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 validating the predictive potential of the Cisplatin-DRP not only in cisplatin-treated patients but also 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, potentially confirming its utility across both drugs. Future research will aim to determine whether the Cisplatin-DRP can predict the effectiveness of combinations of platinum drugs with PD-1/L1 inhibitors.

CHOSA in short

CHOSA Oncology AB is an oncology biotechnology company led by a proven international team with veteran specialists in oncology; drug development; running clinical trials; regulatory expertise; and business development. CHOSA intends to enter into agreements for partnership or sublicensing of LiPlaCis® and the DRP®.

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

CHOSA is advancing its cisplatin Drug Response Predictor - Cisplatin-DRP®, a clinically validated test that identifies which patients are most likely to benefit from cisplatin and carboplatin treatment. The DRP holds global rights and is the only proven tool to guide platin use across cancer types.

In metastatic breast cancer, Phase 2b data show that DRP-selected patients respond better and have longer progression-free survival.
In lung cancer, the DRP has predicted benefit from cisplatin after surgery - especially relevant now that cisplatin is increasingly combined with PD(L)-1 immunotherapies in neoadjuvant settings. In two independent studies, patients with the highest DRP scores had a 3-year survival rate of 90%, compared to just 40% among those with the lowest scores1.

The DRP may help guide combination treatments by predicting who will benefit from platinum-immunotherapy synergy.

Immunotherapy There is a new development that adds further value to our DRP. Platin has often been shown to activate the immune system (making cold tumors hot), which makes tumors susceptible to PD1 inhibitors. This synergy is particularly important but not limited to the treatment of lung cancer, bladder cancer, and head and neck cancer. In the ever-growing PD1 inhibitor market, where competition is fierce, our company stands out with the ability to predict if cisplatin will provide synergy with PD1. This can give the PD1 selling companies a significant competitive advantage.

1) Buhl et al PLOS One doi: 10.1371/journal.pone0194609

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.