The fluoroquinolone program at Bayer focused on examining the effects of very minor changes to the norfloxacin structure. In 1983, the company published in vitro potency data for ciprofloxacin, a fluoroquinolone antibacterial having a chemical structure differing from that of norfloxacin by the presence of a single carbon atom. This small change led to a two- to 10-fold increase in potency against most strains of Gram-negative bacteria. Importantly, this structural change led to a four-fold improvement in activity against the important Gram-negative pathogen Pseudomonas aeruginosa, making ciprofloxacin one of the most potent known drugs for the treatment of this intrinsically antibiotic-resistant pathogen.The oral tablet form of ciprofloxacin was approved in October 1987, just one year after the approval of norfloxacin. In 1991, the intravenous formulation was introduced. Ciprofloxacin sales reached a peak of about 2 billion euros in 2001, before Bayers patent expired in 2004, after which annual sales have averaged around €200 million.The name probably originates from the International Scientific Nomenclature: ci- (alteration of cycl-) + propyl + fluor- + ox- + az- + -mycin. Society and culture
Cost
It is available as a generic medication and not very expensive. At least one company, Turtle Pharma Private Limited provides industrial-size amounts

Generic equivalents
On 24 October 2001, the Prescription Access Litigation (PAL) project filed suit to dissolve an agreement between Bayer and three of its competitors which produced generic versions of drugs (Barr Laboratories, Rugby Laboratories, and Hoechst-Marion-Roussel) that PAL claimed was blocking access to adequate supplies and cheaper, generic versions of ciprofloxacin.
Fludarabine is a purine analogue and antineoplastic agent. It is generally used as its 5-O-phosphorylated form known as fludarabine phosphate,
sold under the brand name Fludara among others. It is a chemotherapy medication used in the treatment of leukemia and lymphoma. These include chronic lymphocytic leukemia, non-Hodgkins lymphoma, acute myeloid leukemia, and acute lymphocytic leukemia. It is given by injection into a vein or by mouth.Common side effects include nausea, diarrhea, fever, rash, shortness of breath, numbness, vision changes, and feeling tired. Severe side effects include brain dysfunction, low blood cell counts, and lung inflammation. Use in pregnancy will likely result in harm to the fetus. Fludarabine is in the purine analog family of medications and works by interfering with the duplication of DNA.Fludarabine was approved for medical use in the United States in 1991. It is on the World Health Organizations List of Essential Medicines. Medical uses
Fludarabine is highly effective in the treatment of chronic lymphocytic leukemia, producing higher response rates than alkylating agents such as chlorambucil alone. Fludarabine is used in various combinations with cyclophosphamide, mitoxantrone, dexamethasone and rituximab in the treatment of indolent non-Hodgkins lymphomas. As part of the FLAG or FLAMSA regimen, fludarabine is used together with cytarabine and granulocyte colony-stimulating factor in the treatment of acute myeloid leukaemia. Because of its immunosuppressive effects, fludarabine is also used in some conditioning regimens prior to allogeneic stem cell transplant. Side effects
Fludarabine is associated with profound lymphopenia, and as a consequence, increases the risk of opportunistic infections.