RedHill's RHB-204 Demonstrates Comparable MAP Killing Efficacy to RHB-104 - Important Step in RHB-204 Development for MAP-related Crohn's Disease
Rhea-AI Summary
RedHill (CPIX) reported in vitro data showing its next-generation oral candidate RHB-204 demonstrates MAP killing comparable to RHB-104, achieved in spot and phage assays and using lower doses of two active ingredients. A Phase 2 trial in MAP-positive Crohn's disease patients is planned, with non-dilutive funding sought and multiple regulatory designations and patent protection through 2041.
AI-generated analysis. Not financial advice.
Positive
- In vitro MAP killing comparable to RHB-104 in spot and phage assays
- Comparable efficacy achieved with lower doses of two active ingredients
- Planned Phase 2 focused on a defined MAP-positive Crohn's disease population
- RHB-104 Phase 3 previously showed clinical remission: 36.7% vs 22.4% (64% relative improvement)
- Patent protection through 2041 and multiple regulatory designations (Fast Track, Orphan, QIDP)
Negative
- RHB-204 comparability shown only in vitro; clinical efficacy in humans not yet demonstrated
- Planned Phase 2 depends on successful MAP detection and non-dilutive funding
- MAP detection is slow and historically difficult, posing trial enrollment and diagnostic risks
- Regulatory benefits cited (breakthrough, priority review) are potential, not guaranteed
News Market Reaction – CPIX
On the day this news was published, CPIX declined 0.48%, reflecting a mild negative market reaction.
Data tracked by StockTitan Argus on the day of publication.
Key Figures
Market Reality Check
Peers on Argus
The stock was down 1.64% while key peers like DRRX, ASRT, CRDL and INCR also showed declines, but none appeared in the momentum scanner and sector momentum was not flagged, suggesting a stock-specific move rather than a broad sector rotation.
Historical Context
| Date | Event | Sentiment | Move | Catalyst |
|---|---|---|---|---|
| Apr 28 | Earnings call timing | Neutral | -1.6% | Announcement of Q1 2026 results release and conference call schedule. |
| Apr 27 | Full-year results | Positive | +3.2% | Full-year 2025 results with strategic deals, cash position and legal win. |
| Apr 23 | Business sale deal | Positive | +27.9% | Agreement to sell U.S. branded business to Apotex affiliate for $100M cash. |
| Apr 22 | Preclinical oncology data | Positive | -2.3% | Opaganib preclinical data enhancing chemo and STING-mediated immunity. |
| Apr 16 | Label expansion | Positive | -3.4% | FDA approval expanding Caldolor injection indication and website launch. |
Positive clinical or strategic news has sometimes aligned with strong gains, but several favorable regulatory or R&D updates saw negative next-day moves, indicating mixed follow-through on good news.
Over recent months, the company’s news flow included a planned Q1 2026 results release, a major $100 million divestiture of U.S. branded assets, and regulatory expansion for Caldolor. Positive strategic transactions drove a strong 27.87% move, while favorable regulatory and pipeline updates at times coincided with declines of 2–3%. The current MAP‑focused Crohn’s data add to this pattern of clinically meaningful announcements set against uneven short-term price reactions.
Market Pulse Summary
This announcement highlights new in vitro data showing RHB‑204’s MAP killing efficacy comparable to RHB‑104, backed by a 331‑patient Phase 3 dataset and a growing Crohn’s market projected from $13.6B to $19.1B. The news fits within a series of clinical and strategic updates that have produced mixed short‑term price reactions. Investors may watch future clinical milestones, regulatory interactions, and partnering or funding developments as key markers of how this program progresses.
Key Terms
mycobacterium avium subspecies paratuberculosis medical
phase 3 medical
phase 2 medical
anti-tnf medical
orphan drug designation regulatory
fast track designation regulatory
qidp designation regulatory
double-blind, placebo-controlled medical
AI-generated analysis. Not financial advice.
RHB-2041 is a next-generation optimized formulation of RedHill's oral RHB-1042, designed for enhanced tolerability, safety profile and patient adherence, that employs a groundbreaking Mycobacterium avium subspecies paratuberculosis (MAP)-targeted therapeutic approach for Crohn's disease (CD)
In its positive Phase 3 study, RHB-104 met the primary and key secondary endpoints with statistical significance, showing RHB-104 plus standard of care (SoC) to be
New RHB-204 in vitro data, from both spot and phage assays, demonstrated comparable MAP killing to RHB-1044. Importantly, MAP killing efficacy was achieved with lower doses of two of the active ingredients compared to RHB-104, indicative of potential for reduced toxicity and side effects
Based on the FDA guidance on path to approval, RedHill's novel Phase 2 RHB-204 study is designed to be the first-ever adequately controlled clinical study in a specifically defined MAP-positive CD patient population - a potentially paradigm changing approach to treatment of Crohn's disease. With discussions ongoing and grant application submitted, funding for this program is planned to be non-dilutive
Expected transferal of RHB-104's FDA pediatric orphan drug designation to RHB-204, potential for breakthrough therapy designation, fast track designation, additional regulatory exclusivity and priority review voucher. RHB-204 is patent protected through 2041, granted FDA Fast Track and Orphan Drug Designation, QIDP Designation under the GAIN Act (extending US market exclusivity to a potential total of 12 years) and EU Orphan Designation (eligibility for 10 years EU market exclusivity) for NTM disease caused by MAC5
The multibillion-dollar CD market is expected to grow from

The comparability results were achieved in both spot and phage assays of several different MAP strains. Importantly, the MAP killing efficacy was achieved with lower doses of two of the active ingredients compared to RHB-104, indicative of the potential for reduced toxicity and side effects.
"As published in the peer-reviewed journal, Antibiotics3, RedHill's RHB-104 had previously delivered positive Phase 3 results showing a statistically significant
A planned Phase 2 study of RHB-204 in CD is expected to be the first clinical study in a specifically defined MAP-positive CD patient population. There is a significant body of peer reviewed published research supporting the scientific rationale that MAP may be a root cause of CD8, however, a major hurdle in previous clinical studies for new therapies directed at MAP has been the ability to rapidly and accurately detect MAP – one of the slowest growing and hard to detect bacteria on the planet. This study, along with RedHill's collaborations with two leading European academic centers for the provision of cutting-edge MAP detection diagnostics, which support the study's novel design and the potential future commercial application of RHB-204, represents a groundbreaking approach that could potentially make RHB-204, if approved, an exciting new therapy treating both the suspected cause of the disease and its symptoms.
RedHill is actively pursuing partnerships and collaborations for this program, including via an innovation development grant application, which has already been submitted. In addition, RedHill is engaging in ongoing discussions with non-dilutive external funding sources.
The development of RHB-204 is supported by a strong foundation of published clinical efficacy and safety data from the randomized, double-blind, placebo-controlled 331-patient Phase 3 study of RHB-104 in active CD, which successfully met its primary and secondary endpoints, showing RHB-104 plus standard of care (SoC) to be
The CD market is expected to expand significantly through 2033, with sales in
About RHB-204
RHB-204 is a proprietary, fixed-dose oral capsule containing a combination of clarithromycin, rifabutin and clofazimine, at specific doses designed to safely and effectively treat Mycobacterium avium subspecies paratuberculosis-positive (MAP-positive)-related Crohn's disease.
Patent protected until at least 2041, and with an expected pediatric orphan designation (subject to the
Originally developed for the treatment of pulmonary non-tuberculous mycobacteria (NTM) disease caused by Mycobacterium avium complex (MAC), RHB-204 was granted FDA Fast Track and Orphan Drug Designation, in addition to QIDP Designation under the Generating Antibiotic Incentives Now Act (GAIN Act), extending
About Crohn's Disease
Crohn's disease (CD) is a form of Inflammatory Bowel Disease (IBD) causing inflammation of digestive tract tissue that can lead to abdominal pain, severe diarrhea, fatigue, weight loss and malnutrition. CD can be highly debilitating and remains a serious burden for both patients and healthcare systems: destroying quality of life and even leading to life-threatening complications. There is no known cure for Crohn's disease. It is estimated that 1 million Americans9 and approximately 6-8 million people globally have Crohn's disease10.
Commonly used FDA-approved therapies in the treatment of CD include: Abbvie's Humira® (adalimumab), Janssen's Remicade® (infliximab) and Stelara® (Ustekinumab), BMS's Zeposia® (ozanimod) and Pfizer's Xeljanz® (tofacitinib).
About RedHill Biopharma
RedHill Biopharma Ltd. (NASDAQ: RDHL) is a specialty biopharmaceutical company primarily focused on U.S. development and commercialization of drugs for gastrointestinal diseases, infectious diseases and oncology. RedHill promotes the FDA-approved gastrointestinal drug Talicia, for the treatment of Helicobacter pylori (H. pylori) infection in adults11, with a
Visit www.redhillbio.com / X.com/RedHillBio for more information about the Company
Forward Looking Statements
This press release contains "forward-looking statements" within the meaning of the Private Securities Litigation Reform Act of 1995 and may discuss investment opportunities, stock analysis, financial performance, investor relations, and market trends. Such statements may be preceded by the words "intends," "may," "will," "plans," "expects," "anticipates," "projects," "predicts," "estimates," "aims," "believes," "hopes," "potential" or similar words, and include, among others, statements regarding the potential transferal of pediatric orphan drug designation to RHB-204, the potential for breakthrough therapy designations, fast track designations, additional regulatory exclusivity and priority review vouchers, the potential for partnerships and funding sources for the development of RHB-204, and the potential success of any transactions, commercial programs or development activities. Forward-looking statements are based on certain assumptions and are subject to various known and unknown risks and uncertainties, many of which are beyond the Company's control and cannot be predicted or quantified, and consequently, actual results may differ materially from those expressed or implied by such forward-looking statements. Such risks and uncertainties include, without limitation: the risk that development of RHB-204 for Crohn's disease may not be completed, or if completed may not be approved or may not achieve commercial success; the risk that opaganib is not effective against the indications for which we develop our products; the risk that RHB-102 (Bekinda) does not effectively reduce GLP-1/GIP-related nausea, vomiting and diarrhea; the risk regarding the Company's ability to regain and maintain compliance with Nasdaq's listing requirements, including the minimum bid price requirement; the risk that the addition of new revenue generating products or out-licensing transactions will not occur; the risk that the Company will not receive future milestone payments under its existing agreements or that they will be less than anticipated; the risk of current uncertainty regarding
Company contact:
Adi Frish
Chief Corporate and Business Development Officer
RedHill Biopharma
+972-54-6543-112
adi@redhillbio.com
Category: R&D
1 RHB-204 is an investigational new drug, not available for commercial distribution in
2 RHB-104 is an investigational new drug, not available for commercial distribution in
3 Graham DY, et al. Randomized, Double-Blind, Placebo-Controlled Study of Anti-Mycobacterial Therapy (RHB-104) in Active Crohn's Disease. Antibiotics (
4 Data on file
5 Non-tuberculous mycobacteria (NTM) lung disease caused by Mycobacterium avium complex (MAC)
6 DataMonitor - Disease Analysis: Crohn's Disease, September 2024
7 Singh S, George J, Boland BS, Vande Casteele N, Sandborn WJ. Primary Non-Response to Tumor Necrosis Factor Antagonists is Associated with Inferior Response to Second-line Biologics in Patients with Inflammatory Bowel Diseases: A Systematic Review and Meta-analysis. J Crohns Colitis. 2018 May 25;12(6):635-643. doi: 10.1093/ecco-jcc/jjy004. PMID: 29370397; PMCID: PMC7189966.
8 Bull T.J., McMinn E.J., Sidi-Boumedine K., Skull A., Durkin D., Neild P., Rhodes G., Pickup R., Hermon-Taylor J. Detection and verification of Mycobacterium avium subsp. paratuberculosis in fresh ileocolonic mucosal biopsy specimens from individuals with and without Crohn's disease. J. Clin. Microbiol. 2003;41:2915–2923. doi: 10.1128/JCM.41.7.2915-2923.2003
9 Lewis JD, Parlett LE, Jonsson Funk ML, et al. Incidence, prevalence, and racial and ethnic distribution of inflammatory bowel disease in
10 Heydari K, Rahnavard M, Ghahramani S, Hoseini A, Alizadeh-Navaei R, Rafati S, Raei M, Vahidipour M, Salehi F, Motafeghi F, Neshat S, Moosazadeh M, Yousefi M, Pourali A, Rasouli K, Shokrirad S, Lotfi P, Beladi SA, Hadizadeh Neisanghalb M, Sheydaee F, Moghadam S. Global prevalence and incidence of inflammatory bowel disease: a systematic review and meta-analysis of population-based studies. Gastroenterol Hepatol Bed Bench. 2025;18(2):132-146. doi: 10.22037/ghfbb.v18i2.3105. PMID: 40936779; PMCID: PMC12421925.
11 Talicia® (omeprazole magnesium, amoxicillin and rifabutin) is indicated for the treatment of H. pylori infection in adults. For full prescribing information see: www.Talicia.com.
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SOURCE RedHill Biopharma Ltd.