Retinitis PigmentosaPhase 3NCT07082855
A Multicenter, Randomized, Double-Blind, Controlled Clinical Study of Minocycline for the Treatment of Retinitis Pigmentosa
A Phase 3 study testing Minocycline 100mg and Minocycline 200mg in people with Retinitis Pigmentosa and Inherited Retinal Dystrophy, run by Zhongshan Ophthalmic Center, Sun Yat-sen University at 1 site in China.
Trial summary
This is a multicenter, double-blind, randomized controlled clinical trial to get high - level evidence on minocycline's efficacy and safety（100mg/d, 200mg/d) for Retinitis pigmentosa and to find the optimal treatment dose. Read more about this study
- Who is it for?
- Ages 18 to 60 years
- Conditions the study is for
- Retinitis Pigmentosa, Inherited Retinal Dystrophy, Retina Disorder
- What is being tested?
- Minocycline 100mg and Minocycline 200mg
- Type of treatment
- Pill or oral medicine
- Could I receive a placebo?
- Yes, some participants may receive a placebo
- How many people
- 126 participants
- Where
- 1 siteChina
- Study dates
- 15 Jul 2025to 30 Jun 2028
- Phase
- Phase 3
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 to 60 years
- All sexes
- No healthy volunteers
- Adult
Who may be able to join
- Age should be between 18 and 60 years old.
- Clinically diagnosed with retinitis pigmentosa, characterized by reduced electroretinogram (ERG) responses and constricted visual fields.
- In at least one eye, the amplitude of the 30Hz flicker ERG under photopic conditions should not be lower than 0 microvolts.
- The best-corrected visual acuity (BCVA, ETDRS) in both eyes should not be lower than 0.
Who cannot join
- Allergic to tetracycline antibiotics.
- Pregnant or breastfeeding.
- Syndromic retinitis pigmentosa.
- Currently taking tetracycline antibiotics or any medications that may have adverse interactions with minocycline.
- Currently participating in or having participated in another investigational study within the past 6 months.
- Presence of other ocular diseases, including glaucoma, uveitis, age-related macular degeneration, diabetic retinopathy, etc.
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- History of ocular surgical intervention.
- History of uncontrolled severe comorbid conditions, such as renal disease, liver disease, autoimmune disease, thyroid dysfunction, psychiatric disorders, or idiopathic intracranial hypertension.
- Inability of the participant to comply with the study-required procedures, such as epilepsy, inability to fixate, or allergy to fluorescein. Inability to understand the content of the study, sign the informed consent form, or comply with the study procedures or follow-up visits.
- Inability to swallow capsules.
Trial locations and contacts
1 site in 1 country. Contact the study team or a site near you to ask about taking part.
China1 site
Zhongshan Ophthalmic Center, Sun Yat-sen University
Guangzhou, Guangdong, 510060
Dan Liang, Professor, 0086-020-87330402, liangdan@gzzoc.com
About this study
Official title: A Multicenter, Double-Blind, Randomized Controlled Clinical Study of Minocycline for the Treatment of Retinitis Pigmentosa
This is a multicenter, double-blind, randomized controlled clinical trial to get high - level evidence on minocycline's efficacy and safety（100mg/d, 200mg/d) for Retinitis pigmentosa and to find the optimal treatment dose.
Read the detailed description
Retinitis pigmentosa (RP) is a major blinding eye disease, with a global prevalence of 1/9000-1/850. It's estimated that over 1.5 million Chinese people may have RP. Its typical clinical features are night blindness and progressive tunnel vision. In the disease's end stage, total loss of peripheral and central vision may occur, accounting for about 20% of all blinding causes. The main characteristic of RP is the progressive apoptosis of retinal photoreceptor cells, which leads to gradually worsening night blindness, concentric visual field constriction, and decreased visual acuity, among other visual function impairments.
The core of RP treatment is to slow down the progression of visual impairment and delay disease advancement. However, currently there are no effective clinical methods or recommended medications to control or slow RP's progression. In recent years, advanced therapies like gene therapy and stem cell treatments have been tried for RP but are still far from clinical application due to technical challenges. So, there's an urgent need for more accessible, widely applicable, and economical treatments.
RP has a complex and poorly understood etiology. Microglia, key resident macrophages in the central nervous system, when activated, can promote neurodegenerative diseases like RP. Suppressing this activation may slow disease progression. Minocycline, a tetracycline antibiotic with anti-inflammatory and immunomodulatory effects, can cross the blood - brain barrier and protect neurons by inhibiting microglial activation. It's been studied for treating neurodegenerative diseases such as Alzheimer's and Huntington's disease. A randomized controlled trial published in The New England Journal of Medicine in 2017 found that 6 months of 200mg daily minocycline for clinically isolated syndrome patients reduced their conversion rate to multiple sclerosis, showing minocycline's potential in neurodegenerative disease treatment. Safety studies indicate no antibiotic resistance after 36 months of 200mg daily minocycline used in geographic atrophy in age-related macular degeneration.
Our team completed a pilot study on minocycline for RP. The results showed that 12 months of 100mg daily minocycline improved RP patients' visual function with good tolerability.
Based on this, we plan a multicenter, randomized, double-blind, controlled clinical trial to get high - level evidence on minocycline's efficacy and safety for RP.
- Being tested
- Minocycline 100mg, Minocycline 200mg, Placebo
- Keywords
- Retinitis Pigmentosa, Minocycline, ERG, Inherited Retinal Dystrophy
- Medical subject headings
- Retinitis Pigmentosa, Retinal Diseases, cyclopia sequence
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Minocycline 100mgDrug
Also called MRP intervention 1
Capsules Minocycline 100mg po per day and placebo 100mg po per day for 12 months
Minocycline 200mgDrug
Also called MRP intervention 2
Capsules Minocycline 100mg po twice a day for 12 months
PlaceboDrug
Also called MRP control
Capsules placebo 100mg po twice a day for 12 months
| Study group | Role | What they receive |
|---|---|---|
| Minocycline 100mg | Experimental | Capsules Minocycline 100mg po once in the morning and placebo 100mg po once in the evening for 12 months Receives: Drug: Minocycline 100mg |
| Minocycline 200mg | Experimental | Capsules Minocycline 100mg po twice a day for 12 months Receives: Drug: Minocycline 200mg |
| Placebo | Placebo comparator | Capsules placebo 100mg po twice a day for 12 months Receives: Drug: Placebo |
What is being measured
The primary outcome is the main question the study is designed to answer.
The change of ERG
The proportion of patients in the group who showed an increase in the amplitude of the light-adapted 30Hz flicker ERG response at 12 months post-treatment compared to baseline.
Measured: 12 months
Secondary outcomes (8)
The change of BCVA
The proportion of patients in this group showing an increase from baseline at month 12 of treatment.
Measured: 12 months
The change of VF
The proportion of patients in this group showing an increase from baseline at month 12 of treatment.
Measured: 12 months
The change of color vision
The proportion of patients in this group showing an increase from baseline at month 12 of treatment.
Measured: 12 months
The change of microperimetry
The proportion of patients in this group showing an increase from baseline at month 12 of treatment.
Measured: 12 months
The change of contrast sensitivity
The proportion of patients in this group showing an increase from baseline at month 12 of treatment.
Measured: 12 months
The change of OCT
The proportion of patients in this group showing an increase from baseline at month 12 of treatment.
Measured: 12 months
The change of NEI-VFQ-25
The proportion of patients in this group showing an increase from baseline at month 12 of treatment.
Measured: 12 months
The change of other ERG amplitude
The proportion of improvement in amplitude in light-adapted 3.0Hz ERG, dark-adapted 0.01Hz ERG and dark-adapted 3.0Hz ERG from baseline at month 12 of treatment.
Measured: 12 months
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted24 Jul 2025
- Study start15 Jul 2025 (estimated)
- Primary completion28 Feb 2028 (estimated)
- Study completion30 Jun 2028 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Retinitis PigmentosaStudies of the same condition, open and under way.
- More trials run by Zhongshan Ophthalmic Center, Sun Yat-sen UniversityThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase 3
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Quadruple blind
- Who is masked
- Participant, Care provider, Investigator, Outcomes assessor
- Enrolment
- 126 participants (estimated)
Sponsor and investigators
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, Liang Dan, Zhongshan Ophthalmic Center, Sun Yat-sen University
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07082855
- Sponsor's protocol ID
- MRP
- Status last verified
- Jul 2025
- First submitted
- 15 Jul 2025
- Last updated
- 24 Jul 2025
- Results posted
- No
- Data monitoring committee
- Yes
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No
Study at a glance
From the registry record, last updated by the sponsor on 24 Jul 2025. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- A Multicenter, Double-Blind, Randomized Controlled Clinical Study of Minocycline for the Treatment of Retinitis Pigmentosa
- ClinicalTrials.gov ID
- NCT07082855
- Acronym / sponsor ID
- MRP
- Keywords
- Retinitis Pigmentosa, Minocycline, ERG, Inherited Retinal Dystrophy
- Phase
- Phase 3
- Study type
- Interventional
- Recruitment status
- Not yet recruiting
- Enrolment
- 126 participants (estimated)
- Lead sponsor
- Zhongshan Ophthalmic Center, Sun Yat-sen UniversityUniversity, hospital or other
- Study start
- 15 Jul 2025 (estimated)
- Primary completion
- 28 Feb 2028 (estimated)
- Study completion
- 30 Jun 2028 (estimated)
- First posted
- 24 Jul 2025 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
This is a multicenter, double-blind, randomized controlled clinical trial to get high - level evidence on minocycline's efficacy and safety（100mg/d, 200mg/d) for Retinitis pigmentosa and to find the optimal treatment dose.
Detailed description
Retinitis pigmentosa (RP) is a major blinding eye disease, with a global prevalence of 1/9000-1/850. It's estimated that over 1.5 million Chinese people may have RP. Its typical clinical features are night blindness and progressive tunnel vision. In the disease's end stage, total loss of peripheral and central vision may occur, accounting for about 20% of all blinding causes. The main characteristic of RP is the progressive apoptosis of retinal photoreceptor cells, which leads to gradually worsening night blindness, concentric visual field constriction, and decreased visual acuity, among other visual function impairments.
The core of RP treatment is to slow down the progression of visual impairment and delay disease advancement. However, currently there are no effective clinical methods or recommended medications to control or slow RP's progression. In recent years, advanced therapies like gene therapy and stem cell treatments have been tried for RP but are still far from clinical application due to technical challenges. So, there's an urgent need for more accessible, widely applicable, and economical treatments.
RP has a complex and poorly understood etiology. Microglia, key resident macrophages in the central nervous system, when activated, can promote neurodegenerative diseases like RP. Suppressing this activation may slow disease progression. Minocycline, a tetracycline antibiotic with anti-inflammatory and immunomodulatory effects, can cross the blood - brain barrier and protect neurons by inhibiting microglial activation. It's been studied for treating neurodegenerative diseases such as Alzheimer's and Huntington's disease. A randomized controlled trial published in The New England Journal of Medicine in 2017 found that 6 months of 200mg daily minocycline for clinically isolated syndrome patients reduced their conversion rate to multiple sclerosis, showing minocycline's potential in neurodegenerative disease treatment. Safety studies indicate no antibiotic resistance after 36 months of 200mg daily minocycline used in geographic atrophy in age-related macular degeneration.
Our team completed a pilot study on minocycline for RP. The results showed that 12 months of 100mg daily minocycline improved RP patients' visual function with good tolerability.
Based on this, we plan a multicenter, randomized, double-blind, controlled clinical trial to get high - level evidence on minocycline's efficacy and safety for RP.
Study design
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Quadruple blind (participant, care provider, investigator, outcomes assessor)
- Number of arms
- 3
| Arm | Type | Receives |
|---|---|---|
| Minocycline 100mg | Experimental | Drug: Minocycline 100mgCapsules Minocycline 100mg po once in the morning and placebo 100mg po once in the evening for 12 months |
| Minocycline 200mg | Experimental | Drug: Minocycline 200mgCapsules Minocycline 100mg po twice a day for 12 months |
| Placebo | Placebo comparator | Drug: PlaceboCapsules placebo 100mg po twice a day for 12 months |
Who may qualify
- Ages
- 18 to 60 years
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult
Key inclusion criteria (4 listed)
- Age should be between 18 and 60 years old.
- Clinically diagnosed with retinitis pigmentosa, characterized by reduced electroretinogram (ERG) responses and constricted visual fields.
- In at least one eye, the amplitude of the 30Hz flicker ERG under photopic conditions should not be lower than 0 microvolts.
- The best-corrected visual acuity (BCVA, ETDRS) in both eyes should not be lower than 0.
Key exclusion criteria (10 listed)
- Allergic to tetracycline antibiotics.
- Pregnant or breastfeeding.
- Syndromic retinitis pigmentosa.
- Currently taking tetracycline antibiotics or any medications that may have adverse interactions with minocycline.
- Currently participating in or having participated in another investigational study within the past 6 months.
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Minocycline 100mgAlso: MRP intervention 1Capsules Minocycline 100mg po per day and placebo 100mg po per day for 12 months | Drug | Minocycline 100mg |
| Minocycline 200mgAlso: MRP intervention 2Capsules Minocycline 100mg po twice a day for 12 months | Drug | Minocycline 200mg |
| PlaceboAlso: MRP controlCapsules placebo 100mg po twice a day for 12 months | Drug | Placebo |
Primary outcome
The change of ERG
Time frame: 12 months
The proportion of patients in the group who showed an increase in the amplitude of the light-adapted 30Hz flicker ERG response at 12 months post-treatment compared to baseline.
8 secondary outcomes
The change of BCVA
Time frame: 12 months
The change of VF
Time frame: 12 months
The change of color vision
Time frame: 12 months
The change of microperimetry
Time frame: 12 months
The change of contrast sensitivity
Time frame: 12 months
The change of OCT
Time frame: 12 months
The change of NEI-VFQ-25
Time frame: 12 months
The change of other ERG amplitude
Time frame: 12 months
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 24 Jul 2025.
- Individual participant dataSharing planned: No
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part.
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A Phase 3 study testing Minocycline 100mg and Minocycline 200mg in people with Retinitis Pigmentosa and Inherited Retinal Dystrophy, run by Zhongshan Ophthalmic Center, Sun Yat-sen University at 1 site in China.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 4 inclusion and 10 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: opening soon, as of the sponsor's last update on 24 Jul 2025. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in China. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. Some participants in this study may receive a placebo. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
What does this phase mean?
Phase 3 studies compare the treatment with the current standard treatment or a placebo in a large group, to confirm how well it works and watch for side effects.
Not every study follows the same path, and some studies (observational studies, device studies) have no phase.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
Contact Dan Liang, Professor (0086-020-87330402, liangdan@gzzoc.com), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
The change of ERG (time frame: 12 months). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 24 Jul 2025.