Having just signed a deal with Argenta Discovery to develop treatments for chronic obstructive pulmonary disease, AstraZeneca has now agreed to acquire another UK biotechnology company, Arrow Therapeutics, for $150 million in cash.

Arrow, which is privately-owned and based in London, specialises in the discovery and development of antiviral therapies. In particular, it has two anti-hepatitis C compounds which both target the novel NS5a protein, including A-831 in Phase I studies, while its most advanced potential treatment, currently in Phase II and partnered with Novartis, is RSV604, a first-in-class, small molecule, oral anti-RSV compound that targets respiratory syncytial virus .

AstraZeneca noted that the deal fits with its recent decision to re-focus its disease area research with infection and anti-bacterials and executive director of development, John Patterson, said the acquisition will add a “world-class anti-viral capability to our own anti-bacterial research capabilities and promising early stage compounds.” The purchase is expected to close in early 2007.

In what has been an extremely busy week for the firm, AstraZeneca also announced that it has signed an R&D agreement with the USA’s Palatin Technologies which could be worth around $300 million to the latter firm.

The companies will work together to discover, develop and sell small molecule compounds that target melanocortin receptors, which could lead to treatments for obesity, diabetes and other ailments. A near-term goal is to select a lead drug candidate for clinical evaluation, according to the companies.

Under the agreement, Palatin will receive an upfront payment of $10 million from AstraZeneca and is eligible for milestone payments totalling $300 million, with up to $180 million contingent upon development and regulatory milestones and the rest on achievement of sales targets, together with the payment of stepped royalties on product sales to double digit rates. The Anglo-Swedish drugmaker, which announces its full-year results later today, will assume responsibility for product commercialisation and development costs, “with both companies contributing their scientific expertise.”