Regulation FD Presentation (Form 8-K)

CAMP4 Presents Translational Data from SYNGAP1-Related Disorders Program Showcasing Increased Protein in Non-Human Primates and Reviews Preclinical and Detailed Single Ascending Dose Safety Data from Urea Cycle Disorders Program at the 28th American Society of Gene and Cell Therapy Annual Meeting

Haploinsufficient SYNGAP1 mice treated with CMP-SYNGAP-01 demonstrated an increase in SYNGAP1 protein levels; treatment rescued multiple SYNGAP1-dependent behavioral phenotypes

CMP-SYNGAP-01 administration led to a significant increase in SYNGAP1 protein levels in relevant brain regions in non-human primates (NHPs)

Patient safety and pharmacokinetic data from single ascending dose (SAD) cohorts of the first-in-human Phase 1 clinical trial of CMP-CPS-001 in healthy volunteers highlighted

CAMBRIDGE, Mass., May 16, 2025 - CAMP4 Therapeutics Corporation ("CAMP4") (Nasdaq: CAMP), a clinical-stage biopharmaceutical company developing a pipeline of regulatory RNA-targeting therapeutics designed to upregulate gene expression with the goal of restoring healthy protein levels to treat a broad range of genetic diseases, today delivered three oral presentations on its SYNGAP1-related disorders and Urea Cycle Disorders (UCDs) programs and shared favorable safety and pharmacokinetics data from the ongoing Phase 1 trial of CMP-CPS-001 in healthy volunteers at the 28th Annual Meeting of the American Society of Gene and Cell Therapy, taking place in New Orleans, May 13 - 17, 2025.

"Patients living with SYNGAP1-related disorders and UCDs currently face a critical dearth of disease-modifying treatment options to manage their condition," said Dan Tardiff, Ph.D., Senior Vice President, Head of Discovery at CAMP4. "These proof-of-mechanism data indicate CMP-SYNGAP-01 can restore SYNGAP1 protein levels to mitigate disease-relevant phenotypes in haploinsufficient mice and increase SYNGAP1 protein in disease-relevant brain regions in non-human primates when delivered by the clinical route of administration. Additionally, our UCD clinical candidate is well tolerated, and we are preparing to evaluate CMP-CPS-001 in OTC heterozygotes, a population with reduced urea cycle function. We're excited to continue pioneering our novel approach of upregulating gene expression and addressing the unmet needs of many patients living with genetic diseases characterized by haploinsufficiency or recessive loss of function."

Josh Mandel-Brehm, Chief Executive Officer of CAMP4, added, "These compelling data underscore the expansive potential of our RAP Platform to address a wide spectrum of genetic conditions, starting with neurologic and metabolic disorders. By pairing clinically validated antisense technologies with newly discovered regulatory RNA targets to upregulate gene expression, we have an opportunity to rapidly advance therapeutics for disorders characterized

by insufficient protein production including SYNGAP1-related disorders, where there is significant unmet need for disease-modifying therapies. We look forward to progressing toward additional clinical trials and exploring strategic partnerships that can accelerate our development plans and deliver long-term value for patients and shareholders."

Key findings for each program are as follows:

SYNGAP1-related disorders program

•In haploinsufficient mice carrying a single copy of the human SYNGAP1 gene, intracerebroventricular (ICV) injection of CMP-SYNGAP-01, a development candidate targeting a regulatory RNA sequence mapped to a SYNGAP1 gene regulatory region, resulted in:

oRestored SYNGAP1 protein levels to near normal range after a single dose

oRescue of motor defects and spatial learning defects following two doses

•In NHPs, biweekly intrathecal injections of CMP-SYNGAP-01 resulted in a ~1.5-fold increase in SYNGAP1 protein levels across multiple brain regions clinically relevant to the disease

oDose-linear increase in CMP-SYNGAP-01 in disease-relevant brain regions

oCMP-SYNGAP-01 was well tolerated

UCD program

•Preclinical data

oIn Otc-deficient mice, treatment with CMP-CPS-001 resulted in dose-dependent reductions in ammonia levels, which persisted for approximately 4 weeks

Increases in mRNA levels of additional enzymes of the urea cycle were observed, suggesting increased metabolic activity

oIn mice with humanized livers, administration of CMP-CPS-001 following an ammonia challenge resulted in increased ureagenesis and decreased ammonia levels

oAdministration of CMP-CPS-001 in NHPs resulted in up to 40% increase in ureagenesis, supporting the MOA to convert ammonia to urea

•Phase 1 clinical data

o48 healthy adult participants were enrolled across four SAD cohorts and randomized 3:1 to a single subcutaneous dose of CMP-CPS-001, with 36 participants randomized to CMP-CPS-001

oCMP-CPS-001 was well tolerated, with no evidence of a maximum tolerated dose and no safety trends of concern

oAll treatment-emergent adverse events (TEAEs) were Grade 1 (mild) or Grade 2 (moderate) with no serious or severe adverse events (AEs) or TEAEs and no participants discontinued study drug due to a TEAE

Most common TEAEs were headache (n=6) followed by nausea (n=4)

oPharmacokinetics

Dose-dependent increase in exposure (Cmax and AUC) with clear separation between dose levels

Greater than dose-proportional increase in exposure (Cmax and AUC0-24)

•Study Update

oDosing complete in MAD Cohort 1 through Cohort 3

oAnticipate expansion into OTC heterozygotes to assess safety and CMP-CPS-001 effect on ureagenesis in patients with evidence of reduced urea cycle function

The presentations can be accessed on the CAMP4 website at https://investors.camp4tx.com/news-events/presentations after the presentations.

About CAMP4 Therapeutics

CAMP4 is developing disease-modifying treatments for a broad range of genetic diseases where amplifying healthy protein may offer therapeutic benefits. Our approach amplifies mRNA by harnessing a fundamental mechanism of how genes are controlled. To amplify mRNA, our therapeutic ASO drug candidates target regulatory RNAs (regRNAs), which act locally on transcription factors and are the master regulators of gene expression. CAMP4's proprietary RAP Platform™ enables the mapping of regRNAs and generation of therapeutic candidates designed to target the regRNAs associated with genes underlying haploinsufficient and recessive partial loss-of-function disorders, of which there are more than 1,200, in which a modest increase in protein expression may have the potential to be clinically meaningful. For more information, visit camp4tx.com.