In October 2005, nelarabine (Arranon; GlaxoSmithKline), a nucleoside analogue, was given accelerated approval by the US FDA for the treatment of patients with T-cell acute lymphoblastic leukaemia and T-cell lymphoblastic lymphoma whose disease has not responded to treatment or has relapsed following treatment with at least two chemotherapy regimens.

In December 2005, abatacept (Orencia; Bristol-Myers Squibb), a fusion protein that selectively modulates a costimulatory signal necessary for T-cell activation, was approved by the US FDA for the treatment of patients with rheumatoid arthritis who have had an inadequate response to other drugs. It is the first selective costimulation modulator to be approved.

In May 2005, galsulfase (Naglazyme; BioMarin), a recombinant form of human N -acetylgalactosamine 4-sulfatase, was approved by the US FDA for the treatment of patients with mucopolysaccharidosis type VI, a rare lysosomal storage disorder caused by a deficiency of N –acetylgalactosamine 4-sulfatase. It is the first approved product for the treatment of mucopolysaccharidosis type VI, and has been granted orphan drug status.

Tigecycline (Tygacil;Wyeth) was approved by the US FDA for the treatment of a range of bacterial infections in June 2005. It is the first in a new generation of tetracyclines known as glycylcyclines, which have been developed to overcome the problems of resistance to earlier tetracyclines.

In April 2005, exenatide (Byetta; Amylin/Eli Lilly) was approved by the US FDA as an adjunctive therapy to improve blood-sugar control in patients with type 2 diabetes. It is the first in a new class of drugs that mimic the activity of natural glucoregulatory peptides known as incretins.