Onyx-15
Onyx 015 is an experimental intratumoral adenovirus, genetically modified from its original cold virus form.[1]
In its unattenuated form, the adenovirus blocks the cell-cycle control protein p53, using the E1B protein, then replicates in the cell it has attacked, and causes lysis, enabling it to spread and infect other cells.
When modified to the Onyx 015 form (E1B-55kDa-deleted), the virus lacks the E1B protein, and so upon infection p53 can block viral replication and initiate cell cycle arrest, and the virus is unable to spread.
However in cancerous cells which lack p53, the virus is still able to replicate. Thus the tumour cells will undergo lysis whilst the healthy surrounding cells are safe.
Chemotherapeutic Use
Onyx 015 has been used experimentally for combatting head and neck tumours, in combination with the standard chemotherapeutic agents cisplatin and 5-fluorouracil [2]
References
- National Cancer Institute definition[3]
- Fadlo R. Khuri, 2000. "A controlled trial of intratumoral ONYX-015, a selectively-replicating adenovirus, in combination with cisplatin and 5-fluorouracil in patients with recurrent head and neck cancer"[4]