Background Niemann-Pick disease, type C1 (NPC1) is a lysosomal storage disorder characterized by progressive neurodegeneration. In preclinical testing 2-hydroxypropyl-β-cyclodextrins (HPβCD) significantly delayed cerebellar Purkinje cell loss, slowed progression of neurological signs, and increased lifespan in murine and feline models of NPC1. Methods Safety and clinical efficacy of intrathecal HPβCD were evaluated in an open-label, dose- escalation phase 1/2a study. Intrathecal doses ranging from 50–1200 mg were evaluated in 14 neurologically affected NPC1 participants treated monthly for 12 to 18 months. Three additional participants were treated every two weeks for 18 months. Serum and CSF 24(S)- hydroxycholesterol, which served as a biomarker of target engagement, and CSF protein biomarkers were evaluated. NPC Neurological Severity Scores (NSS) were used to compare disease progression in HPβCD-treated participants relative to a historical comparison cohort of 21 NPC1 participants of similar age range. Findings No drug-related serious adverse events were observed. Mid- to high-frequency hearing loss, an expected adverse event, was documented. When managed with hearing aids, this did not have an appreciable impact on daily communication. Biomarker studies were consistent with improved neuronal cholesterol homeostasis and decreased neuronal pathology. The NSS score for the 14 participants treated monthly increased at a rate of 122 ± 0 34 points/year compared to 2 92 ± 0 27 points/year (p=0 0002) for the comparison group. Decreased progression was observed for NSS domains of ambulation (p=0 0622), cognition (p=0 0040) and speech (p=0 0423). Interpretation This phase 1/2a study of intrathecal HPβCD for the treatment of NPC1 demonstrated an acceptable safety profile and slowing of disease progression.

Niemann-Pick type C1 (NPC) disease is a lysosomal storage disease caused by mutations in the NPC1 gene, leading to an increase in unesterified cholesterol and several sphingolipids, and resulting in hepatic disease and progressive neurological disease. Whereas subcutaneous administration of the pharmaceutical excipient 2-hydroxypropyl-beta-cyclodextrin (HPβCD) ameliorated hepatic disease, doses sufficient to reduce neurological disease resulted in pulmonary toxicity. In contrast, direct administration of HPβCD into the cisterna magna of presymptomatic cats with NPC disease prevented the onset of cerebellar dysfunction for greater than a year and resulted in a reduction in Purkinje cell loss and near normal concentrations of cholesterol and sphingolipids. Moreover, administration of intracisternal HPβCD to NPC cats with ongoing cerebellar dysfunction slowed disease progression, increased survival time, and decreased the accumulation of brain gangliosides. An increase in hearing threshold was identified as a potential adverse effect. Together, these studies in the feline animal model have provided critical data on efficacy and safety of drug administration directly into the CNS that will be important for advancing HPβCD into clinical trials.

In 2010, the National Institutes of Health (NIH) established the Therapeutics for Rare and Neglected Diseases (TRND) program within the National Center for Advancing Translational Science (NCATS), which was created to stimulate drug discovery and development for rare and neglected tropical diseases through a collaborative model between the NIH, academic scientists, nonprofit organizations, and pharmaceutical and biotechnology companies. This paper describes one of the first TRND programs, the development of 2-hydroxypropyl-β-cyclodextrin (HP-β-CD) for the treatment of Niemann-Pick disease type C1 (NPC1). NPC is a neurodegenerative, autosomal recessive rare disease caused by a mutation in either the NPC1 (about 95% of cases) or the NPC2 gene (about 5% of cases). These mutations affect the intracellular trafficking of cholesterol and other lipids, which leads to a progressive accumulation of unesterified cholesterol and glycosphingolipids in the CNS and visceral organs. Affected individuals typically exhibit ataxia, swallowing problems, seizures, and progressive impairment of motor and intellectual function in early childhood, and usually die in adolescence. There is no disease modifying therapy currently approved for NPC1 in the US. A collaborative drug development program has been established between TRND, public and private partners that has completed the pre-clinical development of HP-β-CD through IND filing for the current Phase I clinical trial that is underway. Here we discuss how this collaborative effort helped to overcome scientific, clinical and financial challenges facing the development of new drug treatments for rare and neglected diseases, and how it will incentivize the commercialization of HP-β-CD for the benefit of the NPC patient community.

Expanded options for treatments directed against pathogens that can be used for bioterrorism are urgently needed. Treatment regimens directed against such pathogens can be identified only by using data derived from in vitro and animal studies. It is crucial that these studies reliably predict the efficacy of proposed treatments in humans. The objective of this study was to identify a levofloxacin treatment regimen that will serve as an effective therapy for Bacillus anthracis infections and postexposure prophylaxis. An in vitro hollow-fiber infection model that replicates the pharmacokinetic profile of levofloxacin observed in humans (half-life [t 1/2 ], 7.5 h) or in animals, such as the mouse or the rhesus monkey (t 1/2 , ϳ2 h), was used to evaluate a proposed indication for levofloxacin (500 mg once daily) for the treatment of Bacillus anthracis infections. The results obtained with the in vitro model served as the basis for the doses and the dose schedules that were evaluated in the mouse inhalational anthrax model. The effects of levofloxacin and ciprofloxacin treatment were compared to those of no treatment (untreated controls). The main outcome measure in the in vitro hollow-fiber infection model was a persistent reduction of culture density (>4 log 10 reduction) and prevention of the emergence of levofloxacin-resistant organisms. In the mouse inhalational anthrax model the main outcome measure was survival. The results indicated that levofloxacin given once daily with simulated human pharmacokinetics effectively sterilized Bacillus anthracis cultures. By using a simulated animal pharmacokinetic profile, a once-daily dosing regimen that provided a human-equivalent exposure failed to sterilize the cultures. Dosing regimens that "partially humanized" levofloxacin exposures within the constraints of animal pharmacokinetics reproduced the antimicrobial efficacy seen with human pharmacokinetics. In a mouse inhalational anthrax model, once-daily dosing was significantly inferior (survival end point) to regimens of dosing every 12 h or every 6 h with identical total daily levofloxacin doses. These results demonstrate the predictive value of the in vitro hollow-fiber infection model with respect to the success or the failure of treatment regimens in animals. Furthermore, the model permits the evaluation of treatment regimens that "humanize" antibiotic exposures in animal models, enhancing the confidence with which animal models may be used to reliably predict the efficacies of proposed antibiotic treatments in humans in situations (e.g., the release of pathogens as agents of bioterrorism or emerging infectious diseases) where human trials cannot be performed. A treatment regimen effective in rhesus monkeys was identified.