UK vaccine maker Acambis’ stock is currently enjoying a boost from a spurt of good news, as settlement of its Arilvax dispute with Swiss drug major Novartis, a new order from the US for its smallpox vaccine and a set of positive clinical trial results has put investors in a good mood. Shares closed up 2.6% at £1.36 on the London Stock Exchange last night, but had risen a further 7.4% to £1.46 in early trading this morning, despite news of a burgeoning loss for the second quarter.

First came the news that Acambis is due to pocket $19 million in cash from Novartis as part of a settlement in the firms’ wrangle over the yellow fever vaccine Arilvax. Acambis was forced to pull its US Arilvax submission in 2004, after its partner Chiron said an upgrade at its manufacturing plant meant that it would not be ready for a necessary inspection by regulators. Novartis inherited the resultant dispute between the firms after swallowing up Chiron earlier this year for $5.1 billion.

Then Acambis announced that the US government has ordered an extra 10 million doses of its smallpox vaccine, ACAM2000, for around $30 million, and said that advanced negotiations are underway for a long-term ‘warm-base’ manufacturing contract, that would see the company supply a batch of the vaccine, once a year, in order to maintain the integrity of the production process and ensure that capacity could be ramped up quickly if required.

“This agreement from the CDC clearly demonstrates the US government’s commitment to ACAM2000 warm-base manufacturing for the long term,” commented Gordon Cameron, Chief Executive of the firm. “Through this order, we can immediately start activities to bring ACAM2000 production entirely in the US. We look forward to securing a long-term warm-base manufacturing contract shortly after the expected licensure of ACAM2000 in early 2007.”

Registration of ACAM2000 will represent the culmination of a breakneck effort to develop an improved smallpox vaccine as part of the USA's bioterrorism defense strategy, set up in the wake of the 09/11 terrorist attacks. Acambis signed a deal to develop the ACAM2000 vaccine with the US government in November 2001, at a time when smallpox was considered the number one threat.

Acambis submitted its Biologics License Application on a rolling basis, starting with the first portion in January 2006. The file includes safety, tolerability and immunogenicity data obtained from clinical trials of ACAM2000 conducted in more than 3,800 subjects.

To date, Acambis has shipped around 180 million doses of ACAM2000 to the US government and received revenues of around $475 million in association with the contract.

In further news, Acambis posted second-quarter sales of £4.6 million, down from the £6.4 million reported for the same period of last year, partially the result of a 40% leap in R&D expenses to £10.5 million. Loss before tax rocketed 63% to £11.4 million, but the group remains confident in its future. “Our development pipeline continues to make good progress with positive clinical news on two of our lead vaccine programmes. With the balance sheet also strengthened following the Arilvax settlement with Novartis, the outlook for Acambis is much improved as we move through the second half of the year,” Cameron said.

On Tuesday, the group reported encouraging data from a mid-stage clinical trial of its West Nile virus, which showed that 97% of participants given the vaccine produced neutralising antibodies, and that the majority of side effects observed were mild in nature.

“These findings will enable us to advance our Phase II trial into older adults, including those within the 50-plus age group who are considered by the US Centers for Disease Control and Prevention to be most at risk from severe disease resulting from West Nile virus infection,’ noted Cameron. This will involve healthy adults aged 41 and over and is designed to assess the safety, tolerability and immunogenicity of ChimeriVax-West Nile compared to placebo. Recruitment is scheduled to start in the fourth quarter of 2006, the group said in a statement.