Metal-based cancer therapies headline ISABC 2023 keynote program

The 16th International Symposium on Applied Bioinorganic Chemistry reaches Ioannina in June 2023, drawing researchers, clinicians and industry partners from across the globe. Among the packed scientific programme, the keynote preview on metal-based drugs in cancer therapy has drawn particular interest. For Australian researchers who have shaped this field for decades, the session offers a chance to see how coordination chemistry continues to reshape modern oncology.

Metal complexes such as cisplatin, carboplatin and oxaliplatin have been cornerstones of cancer chemotherapy since the late twentieth century. Their success spurred a generation of chemists to design next-generation metallodrugs capable of overcoming resistance and targeting tumours more selectively. The keynote arrives when the pipeline of platinum analogues, ruthenium candidates and photoactivatable compounds is finally yielding clinical candidates.

Australia has quietly become one of the most productive nations in this space. Researchers at the Australian Institute for Bioengineering and Nanotechnology in Brisbane, the Peter MacCallum Cancer Centre in Melbourne and the Sydney-based Centenary Institute have all shaped the global metallodrug conversation. Tour de Cure, the Australian cycling-based research charity, has channelled substantial funds into bioinorganic projects, and the Australian Synchrotron in Clayton offers a world-class beamline for studying metal-biomolecule interactions.

The preview is more than a lecture; it is a snapshot of where applied bioinorganic chemistry is heading in the clinic. Understanding which scaffolds are entering trials, which delivery strategies are working and which mechanistic puzzles remain unsolved will help every delegate plan their next experiments and collaborations.

A brief history of metallodrugs in the clinic

Few stories in modern pharmacology match the impact of cisplatin. Discovered in the 1960s and approved for testicular cancer in 1978, the square-planar platinum complex converted a near-uniformly fatal diagnosis into one with cure rates exceeding ninety per cent. That success triggered a thirty-year hunt for analogues, producing carboplatin and oxaliplatin across different jurisdictions.

The limitations of platinum drugs quickly became apparent, with resistance and off-target toxicity affecting the kidneys, peripheral nerves and inner ear. These shortcomings drove Australian medicinal chemists at Monash University and the University of Sydney to explore ruthenium, iridium, gold and titanium scaffolds capable of operating through different biological pathways.

The result is a richer pharmacopeia. Ruthenium(III) complexes such as NAMI-A and KP1339 have reached clinical evaluation, while gold(III) porphyrins and titanocene dichloride derivatives have shown encouraging preclinical activity. Each compound offers a lesson in how ligand design, oxidation state and aquation kinetics shape biological behaviour.

Mechanisms that make metal complexes tick

Unlike purely organic small molecules, metallodrugs bring a built-in set of variables that chemists can tune with atomic precision. A metal centre offers defined coordination geometry, accessible redox potentials and ligand exchange rates that govern how the drug activates inside a tumour cell.

The keynote will explore how modern candidates move beyond simple DNA crosslinking. Photoactivatable ruthenium complexes remain inert in the dark but unleash cytotoxic species when illuminated, opening the door to spatially controlled photodynamic therapy. Iridium(III) complexes can serve as luminescent probes that simultaneously report on intracellular localisation and perturb kinase signalling pathways.

Equally important is the role of the metal itself in determining biodistribution. Platinum drug uptake relies partly on copper transporter CTR1, a relationship Australian biochemists have helped characterise through collaborations with the Peter MacCallum Cancer Centre. Ruthenium mimics iron and can exploit transferrin-mediated endocytosis, granting it selectivity for cancer cells expressing high transferrin receptors.

Emerging candidates heading toward the clinic

The translational pipeline is the most tangible sign of progress. Several compounds discussed at the keynote have either entered phase I trials or are about to file investigational new drug applications. IT-139, a ruthenium-based agent designed to combat resistance in colorectal cancer, has progressed through early safety studies in collaboration with Australian clinical centres.

Photoactive complexes are also advancing. TLD1433, an iridium(III) photosensitiser developed for bladder cancer, has produced striking results when paired with intravesical blue-light illumination, and a follow-on candidate has attracted venture capital from Melbourne's biomedical precinct. Meanwhile, gold(I) complexes bearing N-heterocyclic carbene ligands are progressing through preclinical toxicology at the University of Queensland, supported in part by Cancer Council Australia research grants.

For delegates positioning their own work, the keynote will underline that the bar for clinical translation keeps rising. Regulatory bodies now expect robust pharmacokinetic data and clear evidence of target engagement. This has strengthened ties between chemists, pharmacologists and clinicians, particularly in Australia where collaborative centres offer integrated infrastructure.

Australia's role in the global metallodrug effort

Australia punches well above its weight in bioinorganic cancer research. The country hosts long-running programmes that combine synthetic chemistry with cell biology, structural biology and clinical insight. At the Australian Institute for Bioengineering and Nanotechnology in Brisbane, multidisciplinary teams have pioneered nanoparticle formulations of platinum drugs that reduce neuropathy without sacrificing efficacy. The University of Melbourne's School of Chemistry runs parallel efforts on copper homeostasis in tumours.

Funding pathways matter as much as bench science. The Australian Research Council supports Discovery and Linkage projects that fund metallodrug design across multiple universities, while Cancer Council Australia channels philanthropic donations into translational fellowships. Tour de Cure, famous for cycling fundraisers that cross the Australian outback, has underwritten several bioinorganic grants over the past decade. These mechanisms sustain a research community that is small in population terms but remarkable in output.

International collaboration amplifies the effect. Australian researchers frequently partner with European consortia contributing to the ISABC symposium, and shared access to the Australian Synchrotron in Clayton enables precise spectroscopy of metal-biomolecule adducts. For an Australian delegate attending ISABC 2023, the conference is a natural hub for renewing these partnerships in person.

What the Ioannina keynote will address

The keynote preview is structured as a forward-looking conversation. The speaker will outline three priorities for the coming decade: designing metals that respond to tumour-specific stimuli, integrating metallodrugs with immunotherapy, and building predictive models that link coordination chemistry to patient response. Each priority reflects active investigation in Australian laboratories.

Delegates will also hear about artificial intelligence in ligand design. Machine-learning models trained on existing metallodrug datasets can prioritise scaffolds with favourable solubility, redox behaviour and target affinity, dramatically shortening lead-discovery timelines. This is a method that Australian computational chemists based at the National Computational Infrastructure in Canberra have been refining.

The session will surface unresolved questions about long-term safety, environmental impact and equitable access to expensive new therapies. These concerns shape regulatory decisions and clinical adoption, and by foregrounding them the keynote preview sets the tone for the rest of the symposium programme.

Practical pointers for delegates

• Reserve time for the dedicated poster session on metallodrug design, where early-career researchers from Australian and European labs will present complementary findings.
• Bring a draft abstract if you intend to submit work, following the guidance on the abstracts submission page to meet formatting requirements.
• Identify at least one potential collaborator from a complementary discipline before travelling; the Ioannina venue is compact enough to facilitate informal conversations.
• Plan a visit to the University of Ioannina's chemistry department if you are interested in metallodrug delivery, as the host group has published on liposomal platinum formulations.
• Allocate a half-day after the symposium to explore Ioannina's lake and old town, a refreshing complement to a week of intense scientific exchange.

Delegates, students and industry observers interested in contributing to the conversation can prepare their submissions well in advance. The symposium offers a rare opportunity to present metallodrug research to a focused audience while forming ties with colleagues whose work will shape cancer therapy for years to come.