The University of California, San Diego researched the use of estrogen with two separate drug delivery systems for the prevention of recurrent urinary tract infections (UTIs) in post-menopausal women. Their phase IV clinical trial NCT01958073 had an intervention of 0.5g of estrogen vaginal cream 2 times weekly or an estradiol ring every 3 months for 6 months. More encouraging results were revealed in this trial with vaginal estrogen preventing UTIs in post-menopausal women who have been diagnosed with recurrent UTIs. The University of Southern California is recruiting for its phase II trial NCT04103476 which will look at the effects of a tissue selective estrogen complex therapy on the progression of atherosclerosis and cognitive decline in 360 postmenopausal women aged 45-59 years. The treatment group will receive Bazedoxifene 20 mg/Conjugated Equine Estrogen 0.45 mg for up to a total of 3 years. Measurement outcomes will include carotid artery intima-media thickness, arterial stiffness, and three composite cognitive measures to determine cognitive decline. 677 Aging induces various gut microbiota changes especially the reduction in health promoting species. Researchers in the clinic are looking at gut microbiota modulation for disease treatment of various age-related indications. A few of these studies examined below research the use of pre and probiotics along with fecal microbiota transplant (FMT) to aid a variety of conditions such as immune function, skin health, infection, and neurological disease. One such study sponsored by Clasado discovered that their Bimuno Galacto Oligosaccharide (GOS) mixture product has the potential to increase Bacteroides and Bifidobacterium fecal bacteria during an early phase I clinical trial (NCT01303484). Forty participants (65-80 yrs old) with a dose group of 5 g/day of GOS mixture for 10 weeks revealed that supplementation with a GOS prebiotic positively affects the gut microbiota and biomarkers for immune function amongst the elderly. On the other hand, the University of Antwerp, Belgium saw no immune improvement when looking at the use of Lactobacillus casei Shirota (LcS) probiotic for the prevention of respiratory infection and immune boost in elderly nursing home residents (NCT00849277). 737 volunteers aged 65 and older were enrolled and the treatment group received a daily fermented milk drink that contained greater than 6.5 B live LcS cultures for 176 days with a flu vaccine given on day 21. The results showed no significant effect on the protection against respiratory infections or regarding flu vaccine immune response. Currently in the pipeline, Chr Hansen is recruiting for their research (NCT05529693) on the use of Bifidobacterium adolescentis Bif-038 on low grade inflammation biomarkers. Subjects aged 65-85 years old with low and high treatment groups of 1 and 10 billion CFU for 12 weeks will be tested and various biomarkers such as C-reactive protein and TNFα will be measured. Another method of gut microbiota modulation, FMT, is currently only approved for the treatment of recurrent Clostridioides difficile infection but researchers are branching out and researching its use for other indications with a gut-brain access connection. The University of Ghent has recently completed a clinical trial researching the effect of nasojejunal FMT (NCT03808389) on subjects with Parkinson's disease. 49 subjects aged 50 to 65 were enrolled and the treatment group received donor fecal microbiota with published results forthcoming. 681