CIGB 300

Summary

CIGB‑300 is an investigational cyclic peptide that blocks the activity of protein kinase CK2 by binding to the phospho‑acceptor domain of its substrates. Developed chiefly for locally advanced cervical cancer, it is delivered directly into tumours (intralesional) and has been evaluated in early‑phase clinical studies for safety and preliminary anti‑tumour activity.

Mechanism of Action

CIGB‑300 binds to the phospho‑acceptor region of CK2 substrates, most notably the nucleolar protein B23/nucleophosmin, preventing CK2‑mediated phosphorylation. This disrupts nucleolar integrity, impairs ribosome biogenesis, and triggers caspase‑dependent apoptosis. By inhibiting CK2‑driven signalling pathways that support proliferation, angiogenesis and metastasis, the peptide exerts cytotoxic effects on cancer cells.

What the Research Shows

Pre‑clinical work showed dose‑dependent antiproliferative activity of CIGB‑300 in diverse cancer cell lines and tumour regression after local or systemic administration in mouse models (2008). Proteomic analyses linked the peptide to altered pathways of apoptosis, glycolysis and cell motility (2011). Early clinical trials in women with cervical malignancies demonstrated safety across dose levels up to 490 mg given intralesionally over five days, with local pain, bleeding and erythema as common injection‑site events and occasional rash or facial edema systemically (2009). A phase‑1 dose‑optimization study reported higher tumour uptake and longer half‑life at 70 mg versus 35 mg, down‑regulation of B23/nucleophosmin in tumour biopsies, and no dose‑limiting toxicity, recommending the 70 mg regimen for phase‑2 testing (2015). A 2018 review summarised anti‑angiogenic, antimetastatic and synergistic effects with chemoradiotherapy observed in pre‑clinical models and early clinical settings, but no later‑stage efficacy data have been published.

Reported Benefits

Evidence from early trials indicates that intralesional CIGB‑300 can be administered safely, with no dose‑limiting toxicities observed. Clinical observations include significant lesion reduction in 75 % of patients, complete histologic regression in 19 %, and clearance of HPV DNA in nearly half of previously positive cases. The peptide also down‑regulates the CK2 substrate B23/nucleophosmin in tumour tissue, supporting its intended molecular target engagement.

Limitations of the Evidence

The current evidence is limited to phase‑1 studies involving small cohorts of cervical‑cancer patients; no randomized or controlled trials have been reported. Efficacy outcomes are based on lesion size, histology and HPV status rather than survival endpoints. Systemic administration data are confined to pre‑clinical models, and pharmacokinetic challenges such as rapid diffusion to blood and renal clearance have been noted. Consequently, the therapeutic benefit remains unproven pending phase‑2/3 evaluation.

Safety Considerations

CIGB‑300 has been well tolerated in dose‑escalation studies. The most frequent local adverse events are pain, bleeding, hematoma and erythema at injection sites. Systemic reactions include rash, facial edema, itching, hot flashes and cramps, with allergic‑like responses correlating with transient histamine elevations. No dose‑limiting toxicity or maximum‑tolerated dose was identified, and long‑term follow‑up in early trials reported no recurrences or late adverse effects.

How It Is Administered

In clinical studies the peptide is supplied as a sterile aqueous solution for intralesional injection, typically 0.5 mL per injection site. Dosing regimens have ranged from 14 mg to 490 mg total, administered over consecutive days before standard chemoradiotherapy. Pre‑clinical work also explored intravenous delivery, but human use to date has been limited to direct tumour injection.

Routes of Administration

Goals & Uses

• Inhibition of CK2-driven pro-survival signalingMolecular Target EngagementModerate
• Induction of apoptosis in tumor cellsCellular PharmacologyModerate
• solid tumorsOncologyLow
• Antitumor activity in cervical cancerOncologyModerate
• Antitumor activity in non-small cell lung cancerOncologyLow
• cervical cancerOncologyModerate

Contraindications

• Severe hypersensitivity to peptide componentsAllergy / ImmunologyHigh
• Severe hepatic or renal impairmentOrgan ImpairmentModerate
• PregnancyPopulationHighPotential fetal risk or insufficient safety data
• Hypersensitivity to peptideAllergyHigh

Adverse Effects

• Local Injection Site ReactionsDermatologicalCommon
• Injection site painLocalCommonPain at the injection site
• Fever / flu-like symptomsSystemicUncommon
• NauseaGastrointestinalUncommonFeeling of sickness or urge to vomit
• FatigueGeneralUncommonLow energy or tiredness
• Hematologic toxicityHematologyRare

Drug Interactions

• Cytochrome P450 substratesLow
• Other CK2 inhibitorsModerate
• ImmunosuppressantsLowPotential interaction with immune pathways or infection risk

Population Constraints

• Pediatric patientsAgeRelative
• Pregnant or lactating womenReproductiveRelative
• Pregnant womenReproductiveAbsolute
• Patients with autoimmune disordersImmunologicalRelative

Regulatory Status

• European UnionInvestigationalClinical trials under EMA oversight
• CUInvestigationalDeveloped in Cuba, not yet marketed
• United StatesInvestigationalIND holder, phase I/II trials ongoing
• United KingdomInvestigationalNot approved by MHRA; investigational use only.

Investigational new drug (IND) status in the US and EU; not approved for any indication.

Evidence & Sources

• CIGB-300: A peptide-based drug that impairs the Protein Kinase CK2-mediated phosphorylation
  Journal ArticleModeratePerea SE, et al.2018-01-01T00:00:00.000000Z
• Optimizing CIGB-300 intralesional delivery in locally advanced cervical cancer
  Journal ArticleModerateSarduy MR, et al.2015-01-01T00:00:00.000000Z
• CIGB-300, a synthetic peptide-based drug that targets the CK2 phosphoaceptor domain. Translational and clinical research
  Journal ArticleModeratePerea SE, et al.2011-01-01T00:00:00.000000Z
• Safety and preliminary efficacy data of a novel casein kinase 2 (CK2) peptide inhibitor administered intralesionally at four dose levels in patients with cervical malignancies
  Journal ArticleModerateSolares AM, et al.2009-01-01T00:00:00.000000Z
• Inhibiting CK2 in breast cancer: From molecular targets to drug candidates
  Journal ArticleModerateAl-Zoubi RM, et al.2026-01-01T00:00:00.000000Z
• CIGB-300, a novel proapoptotic peptide that impairs the CK2 phosphorylation and exhibits anticancer properties both in vitro and in vivo
  Journal ArticleModeratePerea SE, et al.2008-01-01T00:00:00.000000Z

Frequently Asked Questions