臨床研究等提出・公開システム

Date of registration	July. 03, 2026
Last modified on	Oct. 13, 2026
Trial ID	jRCT2061260037

Scientific Title	A Phase III study of umedaptanib pegol in children with achondroplasia
Public Title	A Phase III study of umedaptanib pegol in children with achondroplasia

Contact for Scientific Queries	Name	Nonaka Yosuke
	Affiliation	RIBOMIC Inc.
	Address	3-16-13 Shirokanedai, Minato-ku, Tokyo 108-0071, Japan
	Telephone	+81-3-3440-3303
	E-mail	info@ribomic.com
Contact for Public Queries	Name	Nonaka Yosuke
	Affiliation	RIBOMIC Inc.
	Address	3-16-13 Shirokanedai, Minato-ku, Tokyo 108-0071, Japan
	Telephone	+81-3-3440-3303
	E-mail	info@ribomic.com

Recruitment status	Recruiting

Anticipated date of first enrollment		July. 03, 2026
Actual date of first enrollment		July. 01, 2026
Target sample size		16
Study Type		Interventional
Study Design	allocation	non-randomized controlled trial
	masking	open(masking not used)
	control	uncontrolled control
	assignment	single assignment
	purpose	treatment purpose
Key inclusion & exclusion criteria	Inclusion Criteria	(1) Written informed consent has been obtained from a legally acceptable representative (e.g., parents, relatives, or legal guardians) prior to initiation of the study. In addition, the patient has been provided with an explanation of the study using an assent form, and informed assent has been obtained from the patient where possible. (2) Patients who meet the diagnostic criteria and have been diagnosed with achondroplasia (ACH) based on genetic testing, and whose genetic test report is available at the study site. (3) Patients who are aged 2 to 14 years at the time of informed consent. For patients younger than 4 years of age at the time of consent, only those with an annualized height velocity (AHV) =< 3.0 cm/year or those whose AHV is considered stable based on growth records are eligible. (4) Patients who are able to undergo standing height measurements in accordance with the Body Weight, Height, and Anthropometric Measurement Manual. (5) Patients who are able to carry out normal daily activities without assistance. (6) Patients who are considered by the investigator or sub-investigator to be capable of receiving the investigational product and undergoing all study-required procedures as specified in the protocol.
	Exclusion Criteria	(1) Patients diagnosed with disorders other than ACH that may affect height growth velocity. (2) Patients with congenital disorders other than ACH. (3) Patients who have received treatment with growth hormone or vosoritide (Voxzogo) within 4 weeks prior to the start of the study, or who have received other treatments that may affect efficacy evaluation within a specified period prior to the start of the study. (4) Patients who have undergone limb-lengthening surgery within 52 weeks prior to the start of the study. Patients whose external fixation device was removed more than 52 weeks prior to the start of the study are eligible. (5) Patients with closed epiphyseal growth plates. (6) Patients with findings of foramen magnum stenosis, spinal canal stenosis, hydrocephalus, spinal cord or cauda equina compression that may require surgical intervention, or patients with clinically significant neurological symptoms or obstructive sleep apnea resulting from such compression. However, patients who underwent surgical treatment for these conditions more than 52 weeks prior to the start of the study and no longer exhibit clinically significant symptoms are eligible. (7) Patients with a history of hypersensitivity to products containing components of umedaptanib pegol [e.g., oligonucleotides, polyethylene glycol (PEG), mannitol], including prescription drugs, vaccines, over-the-counter drugs, cosmetics, or foods. (8) Patients with a history of cardiac or vascular disease. (9) Patients with clinically significant abnormal findings in hepatic or renal function tests prior to the start of the study. (10) Patients who have experienced fractures of long bones or the spine within 52 weeks prior to the start of the study (excluding fractures of fingers or toes). (11) Patients with a history of hip surgery, severe hip dysplasia, or severe hip injury. (12) Patients who are considered by the investigator or sub-investigator to be unlikely to adequately comply with the administration of umedaptanib pegol or to complete the study. (13) Patients who have used any investigational drug or investigational medical device within a specified period prior to the start of the study. (14) Patients who are otherwise considered by the investigator or sub-investigator to be inappropriate for participation in this study.
	Age Minimum	2age old over
	Age Maximum	14age old under
	Gender	Both
Health Condition(s) or Problem(s) Studied		Achondroplasia
Intervention(s)		After a 26-week observation period, umedaptanib pegol will be administered subcutaneously at a dose of 1 mg/kg once weekly for 52 weeks.
Primary Outcome(s)		(1) Efficacy 1) Primary Endpoint Change in annualized height velocity (AHV) from baseline 2) Secondary Endpoints i) Change in height Z-score from baseline ii) Change in growth parameters and body proportionality from baseline iii) Change in body mass index (BMI) from baseline iv) Change in craniofacial skeletal characteristics from baseline v) Change in spinal and lower limb alignment from baseline vi) Change in quality of life (QOL) from baseline 3) Exploratory Endpoints Change in bone morphology and bone quality from baseline (2) Safety Incidence of adverse events (3) Pharmacokinetics Time course of plasma concentrations of umedaptanib pegol and pharmacokinetic (PK) parameters

Primary Sponsor	RIBOMIC Inc.

Name of Certified Review Board	National Hospital Organization Iwakuni Clinical Center IRB
Address	1-1-1 Atagomachi, Iwakuni-shi, Iwakuni, Yamaguchi, Yamaguchi
Telephone	+81-827-34-1000
Approval Status	Approval
Date of approval	June. 04, 2026

Name of Certified Review Board	Osaka City General Hospital Institutional Review Board
Address	2-13-22, Miyakojimahondori, Osaka Shi Miyakojima Ku, Osaka, Yamaguchi
Telephone	+81-6-6929-3269
Approval Status	Approval
Date of approval	June. 04, 2026

Name of Certified Review Board	Niigata University Medical & Dental Hospital IRB
Address	1-757 Asahimachi-dori, Chuo-ku, Niigata, Niigata, Japan, Yamaguchi
Telephone	+81-25-227-2436
Approval Status	Approval
Date of approval	June. 04, 2026

Name of Certified Review Board	Hiroshima University hospital IRB
Address	1-2-3 Kasumi, Minami-ku, Hiroshima-shi, Hiroshima 734-8551, Japan, Yamaguchi
Telephone	+81-82-257-5596
Approval Status	Approval
Date of approval	June. 04, 2026

Name of Certified Review Board	The Institutional Review Board, The University of Tokyo Hospital
Address	7-3-1 Hongo Bunkyo-ku, Tokyo, Yamaguchi
Telephone	+81-3-5800-8743
Approval Status	Approval
Date of approval	June. 04, 2026

Name of Certified Review Board	Kyushu University Hospital Institutional Review Board
Address	3-1-1 Maidashi, Higashi-ku, Fukuoka-shi, Fukuoka 812-8582, Japan, Yamaguchi
Telephone	+81-92-641-1151
Approval Status	Approval
Date of approval	June. 04, 2026

Name of Certified Review Board	Institutional Review Board of Sapporo Medical University Hospital
Address	291 Minami 1-jo Nishi 16-chome, Chuo-ku Sapporo-shi, Hokkaido 060-0061 Japan, Yamaguchi
Telephone	+81-11-611-2111
Approval Status	Approval
Date of approval	June. 04, 2026

Name of Certified Review Board	Institutional Review Board of Oita University Hospital
Address	1-1 Idaigaoka, Hasama-machi, Yufu, Oita 879-5593, Japan, Yamaguchi
Telephone	+81-97-586-6163
Approval Status	Approval
Date of approval	June. 04, 2026

Name of Certified Review Board	Institutional Review Board of Kyorin University Hospital
Address	6-20-2 Shinkawa, Mitaka-shi, Tokyo 181-8611, Japan, Yamaguchi
Telephone	+81-422-47-5511
Approval Status	Approval
Date of approval	June. 04, 2026

Name of Certified Review Board	Hamamatsu Clinical Research Network Institutional Review Board
Address	2-12-12 Sumiyoshi, Chuo-ku, Hamamatsu-shi, Shizuoka 430-0906, Japan, Yamaguchi
Telephone	+81-53-474-1264
Approval Status	Approval
Date of approval	June. 04, 2026

Name of Certified Review Board	Fukui Prefectural Hospital IRB
Address	2-8-1, Yotsui, Fukui-shi, Fukui, 910-8526, Japan, Yamaguchi
Telephone	+81-776-54-5151
Approval Status	Approval
Date of approval	June. 04, 2026

Name of Certified Review Board	The Institutional Review Board, The University of Osaka Hospital
Address	2-15 Yamadaoka Suita-shi, Osaka 565-0871 Japan, Yamaguchi
Telephone	+81-6-6210-8290
Approval Status	Approval
Date of approval	June. 04, 2026

Name of Certified Review Board	University of the Ryukyus Hospital Institutional Review Board
Address	1076 Aza Kiyuna Ginowan-shi, Okinawa 901-2725 Japan, Yamaguchi
Telephone	+81-98-894-1455
Approval Status	Approval
Date of approval	June. 04, 2026

Name of Certified Review Board	Pediatric Central Institutional Review Board
Address	2-10-1 Okura, Setagaya-ku, Tokyo 157-8535, Japan, Yamaguchi
Telephone	+81-3-5494-7297
Approval Status	Approval
Date of approval	June. 04, 2026

Plan to share IPD	No

Countries of Recruitment（Except Japan）	none

History of Changes

No	Publication date
5	Oct. 13, 2026	(this page)	Changes
4	Aug. 31, 2026	Detail	Changes
3	July. 30, 2026	Detail	Changes
2	July. 06, 2026	Detail	Changes
1	July. 03, 2026	Detail

List of change history