At present, Cerezyme leads the Gaucher’s disease market which, although small, still generates almost 30 per cent of Genzyme’s annual revenues, primarily as a result of the drug’s $200,000 a year price tag.
This domination has continued despite problems at Genzyme’s facility in Allston, Massachusetts that halted production and saw both Protalix and Shire granted special dispensation to supply unapproved competitor drugs to make up for the shortfall.
But while both products are seen as a long-term threat, the prevailing wisdom had been that Cerezyme would maintain its position as market leader for the time being because Shire and Protalix lack the infrastructure to bring their respective products to market in the near future.
Now however, Pfizer’s emergence on the scene may have changed the situation, not least because of the US drug majors’ worldwide reach, as JP Morgan analyst Geoffrey Meacham suggested in a note to clients.
"The improved access to global pharmaceutical markets through Pfizer elevates the Uplyso [taliglucerase alfa] threat to Cerezyme and implies potential downside to Cerezyme"
Others were less convinced, including Leerink Swann’s Joshua Schimmer, who said the Pfizer-Protalix deal was widely expected and should not change assumptions about the Protalix drug's potential to take market share away from Cerezyme.
Genzyme has not yet commented on the Pfizer-Protalix deal.
Under the new licensing deal, which could earn Protalix up to $155m (€103m) before sales, Pfizer can commercialise Uplyso outside Israel, with the Carmiel-headquartered firm retaining the same rights in its home territory.
Even before the Pfizer agreement Uplyso was considered the bigger market threat because, unlike Cerezyme and indeed Shire’s drug, it is manufactured using Protalix’ novel plant-cell based technology that the firm claims is a safer and quicker means of production.
In an allusion to Genzyme’s recent problems Protalix CEO David Aviezer told Newser that:"The minute you use a different cell line, such as a plant cell line…you create a biologic firewall. You totally avoid any risk of cross contamination ... affecting the patient."
Uplyso met primary efficacy endpoints in recently completed Phase III trials, specifically bringing about a reduction in spleen volume from baseline according to results announced in September.
Despite these findings, some have raised concerns about the drug citing the 6 per cent of patients in the trial who developed antibodies and experienced hypersensitivity reactions to Uplyso as something that could derail the drug’s development.
Nevertheless, Protalix said that none of the trial subjects developed neutralizing levels of antibodies and reiterated its plans to file the drug with the FDA in the next few months.
This could mean, if Uplyso is cleared, that we see the drug launched sometime in 2010 at around the same time, if Genzyme’s operations remain virus-free, as supplies of Cerezyme are fully restored.