371P - Adherence to standardized and structured electronic symptom reporting (ePRO) via mobile app in HER2-positive breast cancer treated with HER2 biosimilar trastuzumab

Background

The treatment of HER2+ breast cancer (BC) patients with Herceptin® was the standard for more than a decade. Development of trastuzumab biosimilars has prompted the demonstration of clinical equivalency to the reference biosimilar and safety. So far, adherence to dynamic standardized and structured real-world assessment of wellbeing and symptoms, via ePROs in patients treated with the HER2 biosimilar Ogivri® has not been reported. We assess the adherence of ePROs using the medidux app (previously: consilium care) and perform a comparative analysis of ePROs obtained from HER2+ BC patients in two studies where Herceptin® was administered (NCT02004496, NCT03578731).

Methods

In this 6 week observational study, patients were treated with trastuzumab (Ogivri®) +/- Pertuzumab, +/- Chemotherapy +/- anti-hormones. Patients used the medidux^TM app to record well-being, symptoms (according to CTCAE), EQ-5D-5L, trail maker test and vital parameters and intake of medication in a standardized manner. Patients also received a pop-up reminder in case of missing data entries after 3 days. Previously obtained ePROs from 38 patients treated with Herceptin® similar therapeutic settings were used for comparative analysis.

Results

From 53 female patients included in this trial so far, there was only one drop out. About 60% of patients continued to use the app after the observational 6 weeks period. Close to 10`000 symptom entries were recorded with an average of > 2 symptoms/day. Of the more than 90 individual symptoms, the most common reported were fatigue, taste disorder, diarrhea, nausea, dry mucosa, joint discomfort, tingling, headache and appetite loss. Results available from >70% of all data sets suggests that patients symptoms were reported in a similar incidence and score as from the comparative analysis of Herceptin®. Adherence to the app use and electronic recording of symptoms was continued in average for another 3 months after the end of observation without clear correlation to age or symptom severity.

Conclusions

The majority of patients continued the ePRO app use after end of study participation. Only 1 drop out (from 53 pats) was noted in this propsective observational study.

Clinical trial identification

SNCTP000004711.

Editorial acknowledgement

Legal entity responsible for the study

Mobile Health AG, Zurich.

Funding

Mylan Pharma GmbH (a Viatris Company).

Disclosure

A. Trojan: Other, Personal, Stocks or ownership: Mobile Health AG. All other authors have declared no conflicts of interest.