Fumagillin, an antimicrobial compound first isolated in 1949 from the fungus Aspergillus fumigatusa, naturally occurring water-insoluble antibacterial agent developed by sanofi-aventis, is approved in France for the treatment of microsporidiosis. Fumagillin (Flisint, Sanofi-Aventis, Paris, France) has been approved in France since 2002 for the treatment of intestinal microsporidiosis due to E. bieneusi in patients with AIDS, and is also available through an expanded access program for patients without AIDS. It has not been approved, however, by the US Food and Drug Administration. The discovery of fumagillin, a MetAP-2 inhibitor, with potent antiangiogenic and antiproliferative activities promoted the development of fumagillin analogues as a novel class of anticancer agents. It has been the subject of research in cancer treatments by employing its angiogenesis inhibitory properties.

Xaliproden is an orally active 5HT1-A receptor antagonist that was being developed by Sanofi. It has been evaluated for the treatment of Alzheimer's disease and amyotrophic lateral sclerosis (ALS), and protection against peripheral neurotoxicity associated with certain cancer chemotherapies. Two large, 18-month, clinical trials of xaliproden (monotherapy or adjunctive therapy, respectively) in patients with mild to moderate AD (MMSE, 16–26, inclusive) were completed in 2007. Failure to demonstrate sufficient efficacy in both trials resulted in cancelation of the xaliproden development program for AD in September 2007.

Cefpirome is a semisynthetic, broad-spectrum, fourth-generation cephalosporin with antibacterial activity. Cefpirome binds to and inactivates penicillin-binding proteins (PBPs) located on the inner membrane of the bacterial cell wall. PBPs are enzymes involved in the terminal stages of assembling the bacterial cell wall and in reshaping the cell wall during growth and division. Inactivation of PBPs interferes with the cross-linkage of peptidoglycan chains necessary for bacterial cell wall strength and rigidity. This results in the weakening of the bacterial cell wall and causes cell lysis. Cefpirome is an injectable extended-spectrum or 'fourth generation' cephalosporin. Its antibacterial activity encompasses many of the pathogens involved in hospital-acquired infections such as Enterobacteriaceae, methicillin-susceptible Staphylococcus aureus, coagulase-negative staphylococci and viridans group streptococci. Cefpirome also has in vitro activity against Streptococcus pneumoniae regardless of penicillin susceptibility. It is stable against most plasmid- and chromosome-mediated beta-lactamases, with the exception of the extended-spectrum plasmid-mediated SHV enzymes. Intravenous cefpirome 2g twice daily has shown clinical efficacy comparable to that of ceftazidime 2g 3 times daily in the treatment of hospitalised patients with moderate to severe infections. Clinical response and bacteriological eradication rates were similar in patients with severe pneumonia or septicaemia treated with either cefpirome or ceftazidime. Cefpirome appeared more effective than ceftazidime in the eradication of bacteria in patients with febrile neutropenia in 1 study; however, clinical response rates were similar in the 2 treatment groups. The tolerability of cefpirome appears similar to that of ceftazidime and other third generation cephalosporins, diarrhoea being the most frequently observed event. Thus, cefpirome is likely to be a valuable extended-spectrum agent for the treatment of severe infections. Cefpirome offers improved coverage against some Gram-positive pathogens and Enterobacteriaceae producing class I beta-lactamases compared with the third generation cephalosporins, although this has yet to be demonstrated in clinical trials.