A First-in-human Study of KK8123 in Adults With X-linked Hypophosphatemia

DRUG

KK8123

Subcutaneous administration

Part 1: Number of participants with TEAEs

Time frame: For up to 44 weeks.

Part 1: Percentage of participants with TEAEs

Time frame: For up to 44 weeks.

Part 2: Number of participants with TEAEs

Time frame: For up to 52 weeks.

Part 2: Percentage of participants with TEAEs

Time frame: For up to 52 weeks.

Part 1: Change from baseline for haematology laboratories values

Time frame: For up to 44 weeks.

Part 2: Change from baseline for haematology laboratories values

Time frame: For up to 52 weeks.

Part 1: Change from baseline for clinical chemistry laboratories values

Time frame: For up to 44 weeks.

Part 2: Change from baseline for clinical chemistry laboratories values

Time frame: For up to 52 weeks.

Part 1: Change from baseline in continuous variables for FSH

Time frame: For up to 44 weeks.

Part 2: Change from baseline in continuous variables for FSH

Time frame: For up to 52 weeks.

Part 1: Change from baseline in continuous variables for estradiol

Time frame: For up to 44 weeks.

Part 2: Change from baseline in continuous variables for estradiol

Time frame: For up to 52 weeks.

Part 1: Change from baseline in continuous variables for temperature

Time frame: For up to 44 weeks.

Part 2: Change from baseline in continuous variables for temperature

Time frame: For up to 52 weeks.

Part 1: Change from baseline in continuous variables for pulse rate

Time frame: For up to 44 weeks.

Part 2: Change from baseline in continuous variables for pulse rate

Time frame: For up to 52 weeks.

Part 1: Change from baseline in continuous variables for respiratory rate

Time frame: For up to 44 weeks.

Part 2: Change from baseline in continuous variables for respiratory rate

Time frame: For up to 52 weeks.

Part 1: Change from baseline in continuous variables for systolic and diastolic blood pressure

Time frame: For up to 44 weeks.

Part 2: Change from baseline in continuous variables for systolic and diastolic blood pressure

Time frame: For up to 52 weeks.

Part 1: Change from baseline in continuous variables for QT

Time frame: For up to 44 weeks.

Part 2: Change from baseline in continuous variables for QT

Time frame: For up to 52 weeks.

Part 1: Change from baseline in continuous variables for QTc

Time frame: For up to 44 weeks.

Part 2: Change from baseline in continuous variables for QTc

Time frame: For up to 52 weeks.

Part 1: Change from baseline in continuous variables for QTCF

Time frame: For up to 44 weeks.

Part 2: Change from baseline in continuous variables for QTCF

Time frame: For up to 52 weeks.

Part 1: Change from baseline in continuous variables for QRS

Time frame: For up to 44 weeks.

Part 2: Change from baseline in continuous variables for QRS

Time frame: For up to 52 weeks.

Part 1: Change from baseline in continuous variables for heart rate

Time frame: For up to 44 weeks.

Part 2: Change from baseline in continuous variables for heart rate

Time frame: For up to 52 weeks.

Part 1: The presence or absence of abnormality on ectopic mineralization, any sign of left ventricular hypertrophy or heart failures before and after administration of KK8123 on Echocardiogram

Time frame: For up to 44 weeks.

Part 2: The presence or absence of abnormality on ectopic mineralization, any sign of left ventricular hypertrophy or heart failures before and after administration of KK8123 on Echocardiogram

Time frame: For up to 52 weeks.

Part 1: Before and after administration presented at each time point in categorical variables for renal ultrasound

Time frame: For up to 44 weeks.

Part 2: Before and after administration presented at each time point in categorical variables for renal ultrasound

Time frame: For up to 52 weeks.

Part 1: KK8123 concentrations by maximum plasma concentration (Cmax)

Time frame: For up to 44 weeks.

Part 2: KK8123 concentrations by maximum plasma concentration (Cmax)

Time frame: For up to 52 weeks.

Part 1: KK8123 concentrations by maximum serum concentration (tmax)

Time frame: For up to 44 weeks.

Part 2: KK8123 concentrations by maximum serum concentration (tmax)

Time frame: For up to 52 weeks.

Part 1: KK8123 concentrations by area under the serum concentration time curve from zero to last detectable time point (AUClast)

Time frame: For up to 44 weeks.

Part 2: KK8123 concentrations by area under the serum concentration time curve from zero to last detectable time point (AUClast)

Time frame: For up to 52 weeks.

Part 1: KK8123 concentrations by the area under the serum concentration time curve from zero to infinity (AUC00-inf)

Time frame: For up to 44 weeks.

Part 2: KK8123 concentrations by the area under the serum concentration time curve from zero to infinity (AUC00-inf)

Time frame: For up to 52 weeks.

Part 1: KK8123 concentrations by apparent volume of distribution (V/F)

Time frame: For up to 44 weeks..

Part 2: KK8123 concentrations by apparent volume of distribution (V/F)

Time frame: For up to 52 weeks.

Part 1: KK8123 concentrations by terminal half-life (t1/2)

Time frame: For up to 44 weeks.

Part 2: KK8123 concentrations by terminal half-life (t1/2)

Time frame: For up to 52 weeks.

Part 1: KK8123 concentrations by apparent clearance (CL/F)

Time frame: For up to 44 weeks.

Part 2: KK8123 concentrations by apparent clearance (CL/F)

Time frame: For up to 52 weeks.

Part 1: KK8123 concentrations by maximum plasma concentration steady state (Cmax,ss)

Time frame: For up to 44 weeks.

Part 2: KK8123 concentrations by maximum plasma concentration steady state (Cmax,ss)

Time frame: For up to 52 weeks.

Part 1: KK8123 concentrations by time to maximum serum concentration steady state (tmax,ss)

Time frame: For up to 44 weeks.

Part 2: KK8123 concentrations by time to maximum serum concentration steady state (tmax,ss)

Time frame: For up to 52 weeks.

Part 1: KK8123 concentrations over time by area under the serum concentration curve within a dosing interval at steady state (AUCtau,ss)

Time frame: For up to 44 weeks.

Part 2: KK8123 concentrations over time by area under the serum concentration curve within a dosing interval at steady state (AUCtau,ss)

Time frame: For up to 52 weeks.

Part 1: KK8123 concentrations by time to steady state

Time frame: For up to 44 weeks.

Part 2: KK8123 concentrations by time to steady state

Time frame: For up to 52 weeks.

Part 1: KK8123 concentrations by accumulation ratio

Time frame: For up to 44 weeks.

Part 2: KK8123 concentrations by accumulation ratio

Time frame: For up to 52 weeks.

Part 1: To evaluate the effect of single and multiple SC administrations of KK8123 on serum phosphorus levels

Time frame: For up to 44 weeks.

Part 2: To evaluate the effect of multiple SC administrations of KK8123 on serum phosphorus levels

Time frame: For up to 52 weeks.

What is a clinical trial?

A clinical trial is a research study that tests new medical treatments, drugs, devices, or procedures to determine their safety and effectiveness. Trials are carefully designed and monitored to protect participants while advancing medical knowledge.

Is it safe to participate?

Clinical trials follow strict safety guidelines and ethical standards. Trials must be reviewed and approved, and participants are closely monitored by medical professionals throughout the study. You can withdraw at any time if you choose.

Will I be compensated?

Many clinical trials offer compensation for your time, travel expenses, and inconvenience. The specific compensation varies by study and will be discussed during the screening process. All study-related medical care is typically provided at no cost to participants.

Will I receive a placebo instead of treatment?

When effective treatment exists, participants typically receive either the standard treatment plus the study intervention, or the standard treatment plus placebo. You would not be denied effective care. Placebos are primarily used when no proven treatment is available, or in addition to standard care. Your trial consent form will clearly explain what treatments you may receive.

Can I leave a trial if I change my mind?

Absolutely. Participation in clinical trials is completely voluntary. You have the right to withdraw from the study at any time, for any reason, without penalty or loss of benefits to which you are otherwise entitled.

How long does a clinical trial last?

Trial duration varies widely depending on the study design and purpose. Some trials last just a few weeks, while others may continue for months or years. The study coordinator will provide specific timeline information during your screening call.