Endocrinology

The purpose of this study is to use a randomized, placebo-controlled study design to rigorously examine the therapeutic potential of intermittent hypoxia (IH) for improving cerebrovascular health in older adults with and without type 2 diabetes mellitus (T2DM).

This phase III trial uses the Decipher risk score to guide therapy selection. Decipher score is based on the activity of 22 genes in prostate tumor and may predict how likely it is for recurrent prostate cancer to spread (metastasize) to other parts of the body. Decipher score in this study is used for patient selection and the two variations of treatment to be studied: intensification for higher Decipher score or de-intensification for low Decipher score. Patients with higher Decipher risk score will be assigned to the part of the study that compares the use of 6 months of the usual treatment (hormone therapy and radiation treatment) to the use of darolutamide plus the usual treatment (intensification). The purpose of this section of the study is to determine whether the additional drug can reduce the chance of cancer coming back and spreading in patients with higher Decipher score. The addition of darolutamide to the usual treatment may better control the cancer and prevent it from spreading. Alternatively, patients with low Decipher risk score will be assigned to the part of the study that compares the use of radiation treatment alone (de-intensification) to the usual approach (6 months of hormone therapy plus radiation). The purpose of this part of the study is to determine if radiation treatment alone is as effective compared to the usual treatment without affecting the chance of tumor coming back in patients with low Decipher score prostate cancer. Radiation therapy uses high energy to kill tumor cells and reduce the tumor size. Hormone therapy drugs such as darolutamide suppress or block the production or action of male hormones that play role in prostate cancer development. Effect of radiation treatment alone in patients with low Decipher score prostate cancer could be the same as the usual approach in stabilizing prostate cancer and preventing it from spreading, while avoiding the side effects associated with hormonal therapy.

This phase III trial uses the Decipher risk score to guide therapy selection. Decipher score is based on the activity of 22 genes in prostate tumor and may predict how likely it is for recurrent prostate cancer to spread (metastasize) to other parts of the body. Decipher score in this study is used for patient selection and the two variations of treatment to be studied: intensification for higher Decipher score or de-intensification for low Decipher score. Patients with higher Decipher risk score will be assigned to the part of the study that compares the use of 6 months of the usual treatment (hormone therapy and radiation treatment) to the use of darolutamide plus the usual treatment (intensification). The purpose of this section of the study is to determine whether the additional drug can reduce the chance of cancer coming back and spreading in patients with higher Decipher score. The addition of darolutamide to the usual treatment may better control the cancer and prevent it from spreading. Alternatively, patients with low Decipher risk score will be assigned to the part of the study that compares the use of radiation treatment alone (de-intensification) to the usual approach (6 months of hormone therapy plus radiation). The purpose of this part of the study is to determine if radiation treatment alone is as effective compared to the usual treatment without affecting the chance of tumor coming back in patients with low Decipher score prostate cancer. Radiation therapy uses high energy to kill tumor cells and reduce the tumor size. Hormone therapy drugs such as darolutamide suppress or block the production or action of male hormones that play role in prostate cancer development. Effect of radiation treatment alone in patients with low Decipher score prostate cancer could be the same as the usual approach in stabilizing prostate cancer and preventing it from spreading, while avoiding the side effects associated with hormonal therapy.

This phase III trial compares the effect of low dose tamoxifen to usual hormonal therapy, including aromatase inhibitors, in treating post-menopausal women with hormone positive, HER2 negative early stage breast cancer. Tamoxifen is in a class of medications known as antiestrogens. It blocks the activity of estrogen (a female hormone) in the breast. This may stop the growth of some breast tumors that need estrogen to grow. Aromatase inhibitors, such as anastrozole, letrozole, and exemestane, prevent the formation of estradiol, a female hormone, by interfering with an aromatase enzyme. Aromatase inhibitors are used as a type of hormone therapy to treat postmenopausal women with hormone-dependent breast cancer. Giving low dose tamoxifen may be more effective compared to usual hormone therapy in treating post-menopausal women with hormone-positive, HER2 negative early stage breast cancer.

This phase III trial compares the effect of low dose tamoxifen to usual hormonal therapy, including aromatase inhibitors, in treating post-menopausal women with hormone positive, HER2 negative early stage breast cancer. Tamoxifen is in a class of medications known as antiestrogens. It blocks the activity of estrogen (a female hormone) in the breast. This may stop the growth of some breast tumors that need estrogen to grow. Aromatase inhibitors, such as anastrozole, letrozole, and exemestane, prevent the formation of estradiol, a female hormone, by interfering with an aromatase enzyme. Aromatase inhibitors are used as a type of hormone therapy to treat postmenopausal women with hormone-dependent breast cancer. Giving low dose tamoxifen may be more effective compared to usual hormone therapy in treating post-menopausal women with hormone-positive, HER2 negative early stage breast cancer.

This phase III trial compares the effect of cabozantinib versus combination dabrafenib and trametinib for the treatment of patients with differentiated thyroid cancer that does not respond to treatment (refractory) and which expresses a BRAF V600E mutation. Cabozantinib is in a class of medications called receptor tyrosine kinase inhibitors. It binds to and blocks the action of several enzymes which are often over-expressed in a variety of tumor cell types. This may help stop or slow the growth of tumor cells and blood vessels the tumor needs to survive. Dabrafenib is an enzyme inhibitor that binds to and inhibits the activity of a protein called B-raf, which may inhibit the proliferation of tumor cells which contain a mutated BRAF gene. Trametinib is also an enzyme inhibitor. It binds to and inhibits the activity of proteins called MEK 1 and 2, which play a key role in activating pathways that regulate cell growth. This may inhibit the growth of tumor cells mediated by these pathways. The usual approach for patients with thyroid cancer is targeted therapy with dabrafenib and trametinib. This trial may help researchers decide which treatment option (cabozantinib alone or dabrafenib in combination with trametinib) is safer and/or more effective in treating patients with refractory BRAF V600E-mutated differentiated thyroid cancer.

Gestational Diabetes Mellitus (GDM) currently affects approximately 14% of all pregnancies worldwide. Importantly, the health-related consequences of GDM extend well beyond pregnancy, such that women with a history of GDM have a 40% increased risk of cerebrovascular diseases and a 67% increased risk of dementia, compared to women with a history of uncomplicated pregnancy. Women with a history of GDM have impaired skin microvascular function, compared with women with a history of uncomplicated pregnancy. Therefore, it's likely that GDM results in impaired brain blood vessel function, yet there is little-to-no information regarding the effects of GDM on brain blood vessel health and function after pregnancy.

Therefore, the purpose of the study is to evaluate the effects of GDM on brain blood flow and brain blood vessel function in healthy women with either a history of GDM or uncomplicated pregnancy.

In this study, the investigators will use two different types of ultrasound to non-invasively measure brain blood flow. Brain blood vessel function will be evaluated by examining the brain blood flow responses to increases in carbon dioxide (the increases in carbon dioxide are similar to what is experienced during a breath hold). Additionally, the investigators will compare the brain blood flow results to skin microvascular function to explore potential mechanisms behind possible impairments in brain blood vessel function. Skin microvascular function will be assessed using a minimally invasive technique (intradermal microdialysis for the local delivery of pharmaceutical agents) on dime sized areas of the forearm. Finally, for screening purposes and to further explore potential mechanisms behind any potential impairments in brain blood vessel function, the investigators will perform blood draws to determine the metabolic health of the participants and to analyze for substances that influence blood vessel function.

The goal of this clinical trial is to investigate whether metformin improves vascular function in individuals with prediabetes. The main questions it aims to answer are:

1. Does metformin improve large conduit artery endothelial function in individuals with prediabetes?
2. Does metformin improve microvascular endothelial function in individuals with prediabetes?

Researchers will compare metformin to a placebo to see if metformin improves vascular function in prediabetes.

The trial duration is 12 weeks. Participants will take metformin or a placebo once a day for 2 weeks. After 2 weeks, participants will take metformin or a placebo twice a day for the remaining 10 weeks. There will be a screening visit, two baseline visits, a 4-week safety visit, and two 12-week end-of-study visits. Adherence will be calculated from pill count and adverse events will be quantified via a questionnaire.