Healthy Volunteers - Male and Female

The goal of this clinical trial is to learn if ABS-201 (a new medication) is safe and tolerable when used to improve hair growth in men and women. The trial will start with healthy volunteers and if safe, will treat participants with certain types of hair loss. The main questions it aims to answer are: What medical problems, if any, do participants experience when taking a single dose or many doses of ABS-201? How does the medication, ABS-201, compare to placebo (a look alike substance that does not contain any medication). Participants who qualify for the trial will receive either ABS-201 or a placebo, and visit the study clinic for scheduled checkups and tests for approximately 1 year.

Healthy volunteers aged 18 to 85 will undergo ¹⁹F (perfluoropropane) MRI to support the development of imaging sequences, reconstruction algorithms, and hardware necessary for acquiring high-spatial resolution lung images. The study will also evaluate signal-to-noise ratio, contrast-to-noise ratio, spatial resolution, scan duration, and pulmonary gas exchange measurements derived from ¹⁹F (perfluoropropane) MRI.

Healthy volunteers aged 18 to 85 will undergo hyperpolarized Xenon-129 (¹²⁹Xe) MRI and pulmonary function testing. The study aims to develop evaluation tools for ventilation defect percent (VDP), signal-to-noise and contrast-to-noise ratios (SNR/CNR) of ¹²⁹Xe dissolved-phase images, and spectroscopy-based analysis.

The purpose of this study is to assess the safety and tolerability of ORN252 in healthy adult participants.

The goal of this clinical trial is to evaluate the safety, tolerability, and preliminary characteristics of the investigational drug QLS7305 in healthy adult participants in China. The main questions it aims to answer are: What is the safety and tolerability profile of single and multiple subcutaneous doses of QLS7305 in healthy adults? What are the pharmacokinetic (PK) characteristics of QLS7305 and its major metabolites? What are the pharmacodynamic (PD) effects of QLS7305 on the complement system (e.g., serum C3 levels and complement activity)? Does QLS7305 induce an immunogenic response (anti-drug antibodies)? What is the effect of QLS7305 on the QTc interval? Investigators will compare different dose levels of QLS7305 to a placebo group to see the effects on safety, tolerability, and the measured parameters. Participants will: Be enrolled in one of two parts of the study: Part A (Single Ascending Dose): Receive a single dose of QLS7305 or placebo. Part B (Multiple Ascending Dose): Receive multiple doses of QLS7305 or placebo (doses selected based on Part A results). Receive prophylactic antibiotics (Penicillin V) after the first dose until their serum complement C3 level recovers, as a safety precaution. Undergo close safety monitoring throughout the study, including a follow-up period of up to 337 days to ensure safety parameters return to acceptable levels.

Non-nutritive sweeteners are used as a substitute for simple sugars to improve the palatability of food products without increasing their sugar and calorie content. They represent a global market of 7 billion euros, with an annual growth of 5%. Reducing their consumption therefore seems to be excluded. Some studies have focused on the impacts of these substances on brain activity. According to a recent study, continuous consumption of low doses of saccharin in adult mice significantly decreases the level of dopamine in the prefrontal cortex and significantly increases striatal dopamine, which modifies decision-making strategies. Resting-state functional Magnetic Resonance Imaging (r-fMRI) studies in humans have also shown that an increase in striatal dopaminergic activity modifies the resting-state functional connectivity of brain regions linked to the reward circuit. r-fMRI allows the characterization of brain networks and the strength of correlations between brain regions, without any specific task being required. It is a rapid, non-invasive technique that can measure changes in brain functional connectivity. In addition to r-fMRI, diffusion tensor imaging (DTI) is able to assess white matter microstructure and the integrity or otherwise of fiber tracts. Several parameters such as the fractional anisotropy (FA), coefficient of white matter, mean diffusivity, and radial diffusivity can be modified in the event of changes in functional connectivity, reflecting axonal rearrangements, not visible on conventional MRI sequences. Based on previous research, investigators hypothesize that (1) chronic consumption of non-nutritive artificial sweeteners increases striatal dopaminergic activity. (2) This modification is accompanied by changes in resting-state functional connectivity in brain regions of interest associated with the reward circuit in healthy young adults. Then, the primary objective of this study is to compare, in the resting state, the differences in functional connectivity of brain regions of interest between "non/low consumers" and "high consumers" of sweeteners at the start of the study using r-fMRI. The key secondary objective of this study is to assess changes in brain connectivity using r-fMRI in non- and low-consuming subjects before and after a transient increase in their sweetener consumption over 5 weeks. The secondary objectives include assessing daily sugar consumption (5-week follow-up), daily consumption of non-energy-rich artificial sweeteners (5-week follow-up), Body Mass Index (BMI), physical activity level, and white matter microstructure and fibrous tract integrity using a diffusion-weighted MRI (DTI) sequence.