First-In-Human (FIH), Single Ascending Dose (SAD) Study and Multiple Ascending Dose (MAD) Study of SP-101 Injection

A Phase 1, Randomized, Double-blind, Placebo-controlled, Dose-escalation Study to Assess the Safety, Tolerability, and Pharmacokinetics of SP-101 Injection Following Single and Multiple Intravenous Doses in Healthy Adult Subjects

The goal of this First-In-Human (FIH) trial is to learn about safety, tolerability and pharmacokinetics of single and multiple ascending doses of SP-101 in healthy adult volunteers.

Study Overview

• Status: Not yet recruiting
• Conditions: Major Depressive Disorder, Healthy Volunteer
• Intervention / Treatment: Drug: SP-101 injection; Drug: Placebo

• Study Type: Interventional
• Enrollment (Estimated): 80
• Phase: Phase 1

Contacts and Locations

• Study Contact: Name: HECHUN WANG; Phone Number: +8613911873347; Email: hechunwang@synphatec.com

Study Locations

• China
  • Shanghai Municipality
    • Shanghai, Shanghai Municipality, China, 200030
      • Shanghai Mental Health Center (SMHC)
      • Contact: YIFENG SHEN, M.D.; Phone Number: 86-21-34773657; Email: shenyifeng@yahoo.com
      • Principal Investigator: YIFENG SHEN, M.D.

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

• Willing and able to sign written informed consent;
• Aged 18 to 45 years old (inclusive), healthy males or females (male-to-female ratio is 1:1);
• Efficient contraceptive mean required by the protocol, and no plans for fertility, sperm donation or egg donation until 3 months after the last intravenous infusion;
• Body weight:≥50 kg (Male),≥45 kg (Female), Body Mass Index (BMI) of 18 to 28 kg/m2;
• Normal laboratory tests results, physical examination, medical history and surgical history review, 12-lead Electrocardiogram recording, and with no evidence of active and chronic diseases;
• willing and able to comply with all study procedures, restrictions, and visit schedules and to communicate effectively with the investigator;

Exclusion Criteria:

• Individuals with special dietary requirements who cannot adhere to a unified diet (e.g., intolerance to standard meal foods, or those with dysphagia);
• History of intolerance to IV infusion (e.g., severe pain) or unsuitable venous access (e.g., sclerotic, atrophic veins), difficulties with or contraindications to blood sampling; or a history of needle- or blood-injury-related phobia or syncope;
• Lactation or a positive pregnancy test at screening or baseline;
• Any febrile illness or active infection within 14 days prior to the first dose;
• Evidence of drug / substance abuse within the past 5 years, and/or habitual use of any drugs/substances, or a positive urine drug test at screening or baseline;
• Abnormal renal function (eGFR < 90 mL/min/1.73 m²);
• History of QTc prolongation or demonstration of a clinically relevant ECG abnormality at screening;
• Excessive consumption of nicotine products within 3 months prior to screening (average daily cigarette consumption >5 cigarettes), or inability to stop using any tobacco products during the trial, or a positive nicotine test;
• Previous participation in this study; treatment with an investigational product within 30 days prior to study initiation; or planning participation in another clinical trial during the study period;
• Positive test result at screening for any of the following: hepatitis B surface antigen (HBsAg), antibody to hepatitis C virus (anti-HCV), antibody to human immunodeficiency virus (anti-HIV), or treponemal antibody for syphilis;
• Any abnormal results during screening that is deemed clinically significant by the investigator, e.g., resting pulse <55 or >100 bpm; SBP ≥140 or <90 mmHg; DBP ≥100 or <60 mmHg, or ECG, or abnormal laboratory tests results, clinically relevant;
• Significant blood loss (≥200 mL) within 60 days prior to dosing（including trauma, blood sampling, blood donation, etc.）; or planning blood donation during the study or within 30 days post-dose;
• History of alcohol abuse, or average weekly alcohol consumption greater than 14 units within 3 months prior to screening or a positive alcohol breath test at baseline or inability to abstain from alcohol for the duration of the study;
• Excessive daily consumption of tea, coffee, and/or caffeine-rich beverages for a prolonged period within 3 months prior to screening; or intake of xanthine/caffeine-containing or grapefruit-containing foods or beverages (e.g., coffee, strong tea, chocolate, grapefruit) within 24 hours prior to the first intravenous infusion;
• Using any prescription drugs, OTC medications (excluding hormonal contraceptives, topically applied eye/nose drops and creams with no systemic exposure risk), Chinese herbal medicines, or food supplements such as vitamins and calcium supplements within 14 days prior to screening or during the screening period, unless prior approval has been obtained from the Investigator and Sponsor;
• Using any drugs that inhibit or induce the activity of hepatic drug-metabolizing enzymes within 30 days prior to screening;
• History of a major surgical procedure within the past 6 months prior to screening, or planned elective surgery during the course of the study;
• Current or past history of psychiatric and/or , neurological diseases, and abnormalities of the motor or sensory systems, whether confirmed or suspected;
• Any clinically significant disease, or any clinically significant illness, condition, or other finding that, in the investigator's opinion, would pose a risk to subject safety or interfere with the conduct, progress, or completion of the study.;
• History or current using of hallucinations, which is viewed unsuitable for by investigator;
• History or current presence of psychiatric disorders and/or brain dysfunction;
• History of known or suspected hypersensitivity or allergic reaction to any component of the investigational product or to related compounds, drugs, or foods;
• Any other condition or reason that, in the opinion of the Investigator, would make the subject unsuitable for participation in the study.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Triple

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Investigational Drug group, SP-101 injection; Participants will be randomly assigned to the experimental group and placebo groups at ratio of 3:1. Participants assigned to the experimental group will be administered SP-101 by intravenous infusion. Accordingly, participants assigned to the placebo group will be administered placebo by intravenous infusion.	Drug: SP-101 injection; SP-101 is non-competitive antagonist against NMDA receptor and is administered by intravenous infusion.
Placebo Comparator: Placebo group; Participants will be randomly assigned to the experimental group and placebo groups at ratio of 3:1. Participants assigned to the experimental group will be administered SP-101 by intravenous infusion. Accordingly, participants assigned to the placebo group will be administered placebo by intravenous infusion.	Drug: Placebo; Participants will be randomly assigned to the experimental group and placebo groups at ratio of 3:1. Participants assigned to the experimental group will be administered SP-101 by intravenous infusion. Accordingly, participants assigned to the placebo group will be administered placebo by intravenous infusion.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Time Frame
Treatment Emergent Adverse Events, throughout study completion	Through study completion, an average of 10 days for SAD and an average of 28 days for MAD

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Pharmacokinetic Parameter-AUC₀-inf	Area under the plasma concentration versus time curve (AUC) from time 0 to infinity	From 0 hour before dosing to 72 hours after dosing
Pharmacokinetic Parameter-AUC₀-last	Area under the plasma concentration versus time curve (AUC) from time 0 to the last measurable concentration	From 0 hour before dosing to 72 hours after dosing
Pharmacokinetic Parameter-Cmax	Peak Plasma Concentration (Cmax)	From 0 hour before dosing to 72 hours after dosing
Pharmacokinetic Parameter-Tmax	Time to reach the Peak Plasma Concentration (Tmax)	From 0 hour before dosing to 72 hours after dosing
Pharmacokinetic Parameter-T½	Elimination half life (T½)	From 0 hour before dosing to 72 hours after dosing
Pharmacokinetic Parameter-CL	Apparent clearance (CL)	From 0 hour before dosing to 72 hours after dosing
Pharmacokinetic Parameter- Vz	apparent volume of distribution ( Vz)	From 0 hour before dosing to 72 hours after dosing

Collaborators and Investigators

• Sponsor: Synphatec (Shanghai) Biopharmaceutical Technology Co., Ltd.

Publications and helpful links

Helpful Links

• WHO website has shared some Background information
• Data and information of the marketed drug (Spravato), the same targeting at NMDAR, have been key reference for study design of this protocol.

Study record dates

Study Major Dates

• Study Start (Estimated): December 23, 2025
• Primary Completion (Estimated): June 30, 2026
• Study Completion (Estimated): December 31, 2026

Study Registration Dates

• First Submitted: December 16, 2025
• First Submitted That Met QC Criteria: December 30, 2025
• First Posted (Estimated): January 12, 2026

Study Record Updates

• Last Update Posted (Estimated): January 12, 2026
• Last Update Submitted That Met QC Criteria: December 30, 2025
• Last Verified: December 1, 2025

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Mental Disorders; Mood Disorders; Depressive Disorder; Depressive Disorder, Major
• Other Study ID Numbers: SP-CN_101

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: UNDECIDED

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: Yes
• Studies a U.S. FDA-regulated device product: No