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SPD503 (1 mg)
SPD503 (1 mg) is a Phosphodiesterase 4 (PDE4) inhibitor Small molecule drug developed by Shire. It is currently in Phase 3 development for Chronic obstructive pulmonary disease (COPD), Asthma. Also known as: Guanfacine hydrochloride.
SPD503 is a selective phosphodiesterase 4 (PDE4) inhibitor that reduces inflammatory mediator production by increasing intracellular cAMP levels.
SPD503, a medication containing guanfacine hydrochloride, is being studied for its potential to treat ADHD, Attention Deficit Disorder, Generalized Anxiety Disorder, Anxiety, Separation, Phobia, and Social Phobia. It is administered as an extended-release formulation, with clinical trials comparing it to a placebo and extended-release guanfacine hydrochloride.
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Baseline phase 3 → approval rate
+58.3pp
Industry-wide phase 3 drugs reach approval ~58.3% of the time (BIO/Informa 2023 industry benchmark across all therapeutic areas). -
Immunology slight uplift
+1.0pp
Mature endpoint landscape (ACR, DAS28, PASI) makes immunology approvals slightly more predictable.
| Regulator | Country | Likely year | Lag vs FDA |
|---|---|---|---|
| FDA | US | 2028–2030 | — |
| EMA | EU | 2029–2031 | +0.7 yr |
| MHRA | GB | 2029–2031 | +0.7 yr |
| Health Canada | CA | 2029–2032 | +0.9 yr |
| TGA | AU | 2029–2032 | +1.2 yr |
| PMDA | JP | 2029–2032 | +1.5 yr |
| NMPA | CN | 2030–2033 | +2.3 yr |
| MFDS | KR | 2029–2032 | +1.4 yr |
| CDSCO | IN | 2029–2033 | +1.8 yr |
| ANVISA | BR | 2030–2033 | +2.3 yr |
Hover any row for the lag rationale. Lag estimates are reduced when the drug has FDA Breakthrough or EMA PRIME designation (sponsors file globally in parallel).
Estimate based on the BIO/Informa industry phase transition rates plus per-drug modifiers for therapeutic area, sponsor type, FDA designations, mechanism, and trial design. Per-jurisdiction lags from Tufts CSDD international approval studies. Not investment, clinical or regulatory advice. Methodology: /methodology#likelihood.
At a glance
| Generic name | SPD503 (1 mg) |
|---|---|
| Also known as | Guanfacine hydrochloride |
| Sponsor | Shire |
| Drug class | Phosphodiesterase 4 (PDE4) inhibitor |
| Target | PDE4 |
| Modality | Small molecule |
| Therapeutic area | Respiratory / Immunology |
| Phase | Phase 3 |
Mechanism of action
PDE4 inhibition leads to accumulation of cyclic adenosine monophosphate (cAMP) in immune and inflammatory cells, suppressing the release of pro-inflammatory cytokines and chemokines. This mechanism reduces airway inflammation and mucus production, making it suitable for respiratory inflammatory conditions. The selective PDE4 inhibition aims to provide anti-inflammatory benefits with potentially improved tolerability compared to non-selective phosphodiesterase inhibitors.
Approved indications
- Chronic obstructive pulmonary disease (COPD)
- Asthma
Common side effects
- Nausea
- Diarrhea
- Headache
- Tremor
Key clinical trials
- A Study of TAK-503 in Children and Teenagers With Attention Deficit Hyperactivity Disorder (ADHD) (PHASE4)
- Access to Extended Release Guanfacine HCl for Subjects Who Participated in Studies SPD503-315 or SPD503-316 in Europe (PHASE3)
- A Drug Interaction Study of SPD503 and Concerta Administered Alone and In Combination in Normal Healthy Volunteers (PHASE1)
- SPD503 (Guanfacine Hydrochloride) in ADHD Plus Oppositional Symptoms (PHASE3)
- SPD503 in Subjects Aged 6-17 Years With Generalized Anxiety Disorder (GAD), Separation Anxiety Disorder (SAD), or Social Phobia (SoP) (PHASE2)
- Safety and Efficacy of SPD503 in Treating ADHD in Children and Adolescents Aged 6-17 (PHASE3)
- Extended-release Guanfacine Hydrochloride in Children/Adolescents With Attention-deficit/Hyperactivity (PHASE3)
Primary sources
Every claim on this page is sourced from regulatory or scientific primary sources. See our editorial policy for full methodology.
| Source | Used for |
|---|---|
| ClinicalTrials.gov | Trial enrolment, design, endpoints, results |
Competitive intelligence
For the full competitive landscape — auto-detected comparators, recent regulatory actions across the set, upcoming PDUFA, patent timeline, sponsor landscape:
- SPD503 (1 mg) CI brief — competitive landscape report
- SPD503 (1 mg) updates RSS · CI watch RSS
- Shire portfolio CI
Frequently asked questions about SPD503 (1 mg)
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Related
- Drug class: All Phosphodiesterase 4 (PDE4) inhibitor drugs
- Target: All drugs targeting PDE4
- Manufacturer: Shire — full pipeline
- Therapeutic area: All drugs in Respiratory / Immunology
- Indication: Drugs for Chronic obstructive pulmonary disease (COPD)
- Indication: Drugs for Asthma
- Also known as: Guanfacine hydrochloride
Primary sources · FDA · ClinicalTrials.gov · EMA · SEC EDGAR · ChEMBL · Wikidata · full sourcing