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Zellweger syndrome, also known as cerebrohepatorenal syndrome, is an autosomal recessive peroxisome biogenesis disorder that is part of the family of Zellweger spectrum disorders. It is caused by a defect in one of 12 or more of the PEX genes (PEX1, 2, 3, 5, 6, 10, 12, 13, 14, 16, 19 and 26) that produce proteins called peroxins. Peroxins are used in the formation of peroxisomes, and can be involved in recognition of proteins targeted for the peroxisome, as well as their transport into the peroxisome. Peroxisomes typically break down both very long chain and branched fatty acids, but if they aren't present, these fatty acids build up in the blood and body, harming organs such as the brain and liver. Additionally, due to the fact that some processes, such as plasmalogen biosynthesis, occur in or using peroxisomes, and can lead to deficiencies in plasmalogens. These are important in brain and lung function, leading to other symptoms. Zellweger syndrome is characterized by an increase in levels of very long chain fatty acids in the blood plasma, as well as more visible physical symptoms, such as an abnormally large or small head at birth, characteristic facial features and poor muscle tone, which can lead to an inability of infants to feed. Other symptoms include an enlarged liver, skeletal abnormalities and low CNS function. Infants very rarely live longer than one year, and the only treatment is for symptoms the patient is experiencing, not for the syndrome itself.

The discovery of AIDS prompted the search for agents that block the HIV replication process. Zidovudine (AZT) is a nucleoside analogue of thymidine, and was shown to reduce considerably the mortality of patients with AIDS. Zidovudine is toxic to the hemtopoietic system, causing anemia and neutropenia. It is clear, however, that disease progression can occur during continued administration of zidovudine. Moreover, zidovudine is not effective in treating Kaposi sarcoma, a common complication of HIV infection. Zidovudine therapy is also associated with a high incidence of toxicity, primarily bone marrow suppression, that requires dosage reduction or discontinuation of the therapy.

Zoledronate (also named zoledronic acid, Zometa or Reclast) is a type of medication that used to treat numbers of bone diseases because of its affinity for hydroxyapatite. Zoledronate targets farnesyl pyrophosphate (FPP) synthase by inhibiting the function of this enzyme in the mevalonate pathway, which prevent the biosynthesis of Geranyl-PP and farnesyl pyrophosphate. Geranyl-PP and farnesyl pyrophosphate are important for geranylgeranylation and farnesylation of GTPase signalling proteins. Lack of Geranyl-PP and farnesyl pyrophosphate will result in decreased rate of bond resorption and turnover as well as block the osteoclast activity, which lead to an increasing mass gain in bone (i.e. net gain in bone mass).