Cancer therapy technology has 'potential', says ASH
A research paper demonstrating the potential of Norwegian cancer therapeutics company Algeta's TH-1 technology for targeted cancer therapy has been published by the medical journal, Blood, the official journal of the American Society of Hematology (ASH).
A research paper demonstrating the potential of Norwegian cancer therapeutics company Algeta's TH-1 technology for targeted cancer therapy has been published by the medical journal, Blood, the official journal of the American Society of Hematology (ASH).
Algeta's TH-1 technology links Thorium-227, which emits alpha particles, to cancer-targeting molecules such as antibodies. Alpha-emitting radionuclides are of considerable interest in the treatment of cancer as they are highly destructive to tumour cells but have very short range. Linking this radionuclide to tumour-seeking molecules creates a conjugate with the potential to specifically seek and destroy cancers while leaving surrounding healthy tissues undamaged.
Researchers and Algeta have linked Thorium-227 to the monoclonal antibody rituximab to create 227Th-rituximab and demonstrated its potent anti-tumour effects.
Rituximab binds to a specific molecule on the cancer cell surface called CD20 and is marketed in the USA as Rituxan by Genentech and Biogen-Idec for the treatment of certain types of non-Hodgkin's lymphoma (NHL) and rheumatoid arthritis, and as MabThera by Roche for the treatment of certain types of NHL. Rituximab-based therapies generated global sales of nearly US$6bn in 2006.
In in vitro studies 227Th-rituximab killed CD20-positive lymphoma cells at low doses (Bq/ml) while in preclinical models, a single injection of 227Th-rituximab induced complete tumor regression in up to 60% of tumours without apparent toxicity.
Therapy with 227Th-rituximab was significantly more effective than the control radioimmunoconjugate 227Th-trastuzumab, which does not bind CD20, and the standard beta particle emitting radioimmunoconjugate for CD20-positive lymphoma, Zevalin (90Y-tiuxetan-ibritumomab).
Thomas Ramdahl, president and ceo of Algeta, said: 'This important paper provides more evidence of the potential of alpha particle based molecules for targeted cancer therapy. The publication follows excellent Phase II clinical data for our lead product Alpharadin (radium-223) in prostate cancer, which was published recently in the Lancet Oncology.'