The monoclonal antibody (mAb) Sphingomab therapeutic, targets the Sphingosine-1-phosphate (S1P) lipid, which regulates cell growth, cell survival, cell invasion and new blood cell formation.
Dr Sabbadini, the founder and chief scientific officer of Lpath, and listed inventor in the patent, told DrugResearcher.com: "Sphingomab neutralises the lipid so that it doesn't bind to its compliment of receptors on tumour cells and endothelial cells. Thus, the mAb prevents S1P's tumourigenic effects (growth, metastasis, etc.) and prevents tumour angiogenesis, respectively."
The profound anticancer effects of the lipidomic therapy observed in preclinical studies were published in the March 2006 edition of 'Cancer Cell'. Pilot studies in mice have shown that the antibody also exhibits favorable pharmacokinetic and toxicological profiles.
One of the advantages of targeting bioactive lipids is that, unlike many protein targets, lipid structures do not change significantly between species, suggesting that the efficacy of these preclinical trials in animal models should correlate more closely to results observed in humans.
"This broad patent helps to secure Lpath's proprietary position with regard to Sphingomab and other S1P-binding agents for the treatment of cancer," continued Dr Sabbadini.
"This also represents a major milestone in our efforts to develop this powerful drug candidate for the treatment of cancer and other serious diseases."
Sphingomab is Lpath's lead drug candidate, and is the front-running therapy based on the lipidome technology. Their next in-line drug candidate is Lpathomab, which is an antibody for lysophosphatidic acid (LPA), which is being investigated for cancer and cardiovascular indications.
A recent paper published in November 6th issue of the 'British Journal of Cancer' highlighted the protein-centric nature of the drug development industry. Almost all drugs currently on the market target proteins, with nucleic acids, the next largest category, comprising only two per cent of drug targets.
The field of lipidomics focuses on the study of bioactive lipids and their roles in both normal and pathological signaling pathways.
Dr Sabbadini told DrugResearcher.com that the field of lipidomics is not nearly as well developed as the fields of genomics and proteomics, "but there are a few academic groups pursuing this, such as Ed Dennis at UCSD and Al Merrill at Georgia Tech. To our knowledge, no pharma company has pursued this."
"The antibodies are mouse (murine) mAbs that become humanized by a well-known process that has resulted in producing several therapeutic mAbs that are now on the market,"continued Dr Sabbadini.
"Sphingomab acts similarly to Abbot's Humira and Genentech's Avastin in that they are molecular sponges that neutralize a ligand so that it cannot bind to receptors on target cells."
"Humanized mAbs like Sphingomab have about 95 per cent human sequences. The complementary determining regions (CDRs) come from the murine mAbs and get 'grafted' into a human IgG framework so that the patient doesn't recognize the drug as being other than a human antibody in the circulation."
Lpath expect the US Food and Drug Administration (FDA) to approve the "humanised" version of Sphingomab for a Phase 1 human clinical trial by the end of the 2007. The company expects that the clinical trials stage will take between three to five years.