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L-lysine
L-lysine is an essential amino acid that serves as a protein building block and may have antiviral properties, particularly against herpes simplex virus.
L-lysine is an essential amino acid that serves as a protein building block and may have antiviral properties, particularly against herpes simplex virus. Used for Herpes simplex virus infection (cold sores, genital herpes) — prophylaxis and treatment, General immune support and protein supplementation.
At a glance
| Generic name | L-lysine |
|---|---|
| Also known as | Lysine |
| Sponsor | University of Zurich |
| Drug class | Amino acid supplement |
| Modality | Small molecule |
| Therapeutic area | Infectious disease / Immune support |
| Phase | FDA-approved |
Mechanism of action
L-lysine is one of the nine essential amino acids required for protein synthesis and various metabolic functions. It is thought to inhibit herpes simplex virus replication by competing with arginine, another amino acid that the virus requires for replication. L-lysine is available as a dietary supplement and is marketed for immune support and management of herpes outbreaks.
Approved indications
- Herpes simplex virus infection (cold sores, genital herpes) — prophylaxis and treatment
- General immune support and protein supplementation
Common side effects
- Gastrointestinal upset
- Nausea
- Abdominal pain
Key clinical trials
- Testing the Addition of an Individualized Vaccine to Durvalumab and Tremelimumab and Chemotherapy in Patients With Metastatic Triple Negative Breast Cancer (PHASE2)
- 177Lu-DOTA-EB-TATE in Adult Patients With Metastatic, Radioactive Iodine Non-Responsive Oncocytic (Hurthle-Cell) Thyroid Cancer (PHASE1, PHASE2)
- A Study to Evaluate the Safety, Efficacy, and Pharmacodynamics of PLL001 in ALS Patients (PHASE1, PHASE2)
- Essential Amino Acids and Parkinsons Disease (PHASE1)
- Personalized Neo-Antigen Peptide Vaccine for the Treatment of Stage IIIC-IV Melanoma, Hormone Receptor Positive HER2 Negative Metastatic Refractory Breast Cancer or Stage III-IV Non-Small Cell Lung Cancer (PHASE1)
- NEPC Study: An Exploratory Safety and Efficacy Study With PSMA, SSTR2 and GRPR Targeted Radioligand Therapy in Metastatic Neuroendocrine Prostate Cancer. (PHASE1)
- A Study of Tazemetostat With Enzalutamide or Abiraterone/Prednisone in Participants With Advanced Prostate Cancer (PHASE1, PHASE2)
- SMART Diets for MASLD (PHASE2)
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:
- L-lysine CI brief — competitive landscape report
- L-lysine updates RSS · CI watch RSS
- University of Zurich portfolio CI