Written by Lidiia Zhytnik, member of OIFE’s Scientific Advisory Board

From 24-27 April, the 53rd European Calcified Tissue Society (ECTS) Congress brought together clinicians and researchers working in bone and related conditions. Around 700 participants from Europe and beyond attended. The Osteogenesis Imperfecta Federation Europe (OIFE) was invited to the congress and represented by advisory board member Lidiia Zhytnik.

Focus on OI

OI and other rare bone diseases were at the centre of the congress, with many talks from both the clinical and basic research sides. The open forum, “How to conduct clinical trials in adults with rare disorders: Osteogenesis Imperfecta”, was organised by the Nordic OI clinicians group, chaired by Dr Jannie Dahl Hald and Dr Sigridur Björnsdottir. The session covered: Existing and emerging therapies for Osteogenesis Imperfecta (Dr Jannie Dahl Hald); European research networks and collaboration opportunities (Dr Lena Lande Wekre); Drug repurposing in rare bone disease (Dr Stuart Ralston); Ongoing and future therapies including TGF-beta and sclerostin/DKK1 antibodies (Dr Bente Langdahl).

Lidiia highlighted the role of patient organisations in initiating and supporting research, and the importance of meaningful patient involvement across research, clinical trials and regulatory processes. An “OI meets AI” talk by Mikkel Pretorius explored how AI tools may help summarize research and identify future directions, including gene therapy as a potential long-term avenue.

Clinical discussions

We were delighted to see how much knowledge was shared on OI during the congress. Dr Adalbert Raimann (Austria) raised awareness on OI with nurses and allied health professionals during dedicated seminar. Meet-the-expert session with Dr Stuart Ralston, treatment of OI and existing therapies were discussed. A lively discussion regarding BMD relevance to fracture risk, as well as bisphosphonate treatment in adult patients, took place in the light of recent results from clinical trials (TOPAZ, ORBIT, COSMIC).

Clinical researchers also showed that postmenopausal women with OI benefit less from romosozumab treatment compared to women with osteoporosis. The increase in BMD was seen only in the spine, but not in the hip, and there was no clear improvement in bone microstructure.

Basic science updates

Updates were also shared by basic researchers. They looked into soft tissues in a type 1 mouse model (very few changes in skin and muscle, but some in tendons), investigated osteoarthritis in OI (suggesting changes originate from bone rather than cartilage), studied bone and collagen overmineralization using zebrafish and mouse models, and examined aging in OI mice (lung and heart problems increase with age).

Scientists also presented lab-grown OI bone models (patient bone cell-derived 3D-printed organotypic models) and treated them with a DKK1 antibody, which is the same approach currently being tested by Angitia in clinical trials. The lab-grown bone showed fewer fractures after treatment.

One of the most intriguing talks was by Dr. Guillaume Mabilleau (France). His group tested gut hormone analogues GIP/GLP-2 to treat OI type 3. It was already known that these hormones can improve bone material and collagen, but researcher combined them together into a new special molecule. However, it did not increase BMD, yet mice experienced 92% fewer fractures, which sounds unbelievable. Bone strength increased by 20%, as collagen quality improved after treatment. We are very much looking forward to hearing further updates and developments.

In addition to advances in OI and osteoporosis treatment, new discoveries in basic bone biology, bone cells and stem cells, as well as many new scientific techniques were discussed, inspiring new research that will hopefully be translated into therapies.

For those who would like to dive deeper into the science, the abstracts from the congress are published in the JBMR Plus journal supplement.

During the congress, OIFE also briefly participated in the ECTS highlights episode of the Bone Up! podcast by Dr Richie Abel and Prof David Armstrong, which will be out later this summer. The podcast series are available here.