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CFPS Research Archives

IO102-IO103 (Peptide Vaccine)

Human clinical Immune Support 2 sources

IO102-IO103 is an investigational therapeutic cancer vaccine designed to target and destroy immunosuppressive cells and tumor cells expressing IDO and PD-L1. Research indicates that when combined with immune checkpoint inhibitors, it can significantly enhance anti-tumor immune responses, particularly in advanced melanoma.

01Dosing reference

Amount
Clinical trial specific dosing (e.g., 100-300 mcg per peptide) via SubQ injection
Frequency
Administered on specific days (e.g., days 1, 8, 15, 22, then every 3 weeks)
Cycle
Ongoing alongside checkpoint inhibitor therapy, as per trial protocol
Reference figures, not a recommendationThese values reflect amounts described in the literature and vendor documentation this database indexes. Use the reconstitution calculator to convert them into syringe units.

02Mechanism of action

01

Antigen Presentation

The peptide vaccine introduces IDO and PD-L1 derived peptides to the immune system, which are taken up by antigen-presenting cells.

02

T-Cell Activation

Specific T cells are activated and expand to recognize cells expressing high levels of IDO and PD-L1.

03

Tumor Microenvironment Modulation

The activated T cells target and eliminate both tumor cells and immunosuppressive cells in the tumor microenvironment, enhancing overall anti-tumor immunity.

03Human evidence

High objective response rates in advanced melanoma when combined with nivolumab.

Phase 1/2 clinical trial involving patients with metastatic melanoma showed an objective response rate of up to 80% with the combination therapy.

Favorable safety profile with manageable side effects.

Clinical studies have demonstrated that the vaccine is generally well-tolerated, with most adverse events being mild injection site reactions.

04Preclinical evidence

Synergistic effects with PD-1 blockade.

Animal models of cancer demonstrated that targeting IDO/PD-L1 specific T cells enhances the efficacy of anti-PD-1 therapy.

Depletion of immunosuppressive cells.

In vitro and in vivo studies showed that vaccine-induced T cells can directly kill regulatory T cells and myeloid-derived suppressor cells.

05What is known vs. unknown

Reasonably established
  • Targets both IDO and PD-L1, which are key proteins involved in tumor immune evasion.
  • Designed to be used in combination with standard-of-care immune checkpoint inhibitors.
  • Has received Breakthrough Therapy Designation from the FDA for advanced melanoma.
  • Currently being evaluated in Phase 3 clinical trials for melanoma and Phase 2 trials for other solid tumors.
Unknowns & limits
  • Long-term survival benefits and duration of response in larger patient populations are still being evaluated in Phase 3 trials.
  • Efficacy as a monotherapy or in tumor types with low IDO/PD-L1 expression remains uncertain.
  • Optimal dosing schedules and potential resistance mechanisms require further investigation.

06Safety & regulatory context

Regulatory statusIO102-IO103 is an investigational drug and is not yet FDA-approved for general use. It has received Breakthrough Therapy Designation for unresectable or metastatic melanoma. In clinical trials, it has shown a manageable safety profile, with the most common side effects being mild to moderate injection site reactions, fatigue, and fever. Because it stimulates the immune system, there is a potential risk of immune-related adverse events, especially when combined with checkpoint inhibitors.

07Compared with Pembrolizumab (Anti-PD-1)

IO102-IO103 (Peptide Vaccine) vs. Pembrolizumab (Anti-PD-1)
Key difference
Pembrolizumab is an antibody that blocks the PD-1 receptor to prevent T-cell exhaustion, while IO102-IO103 is a vaccine that actively stimulates T cells to seek out and destroy cells expressing PD-L1 and IDO.
When researchers discuss each
Pembrolizumab is discussed as a standard-of-care checkpoint inhibitor that releases the 'brakes' on the immune system, whereas IO102-IO103 is discussed as a novel combination therapy to actively drive T cells into the tumor microenvironment.

08Glossary

IDO (Indoleamine 2,3-dioxygenase)
An enzyme produced by some tumors and immune cells that suppresses the immune response, helping cancer evade detection.
PD-L1
A protein on the surface of cells that, when bound to PD-1 on T cells, signals the immune system not to attack.
Tumor Microenvironment
The normal cells, molecules, and blood vessels that surround and feed a tumor, often manipulated by the cancer to suppress immune attacks.

09Knowledge check

Q1What is the primary mechanism of action for the IO102-IO103 vaccine?
Q2Which of the following is a key component of the tumor microenvironment targeted by IO102-IO103?
Q3The dossier reports an objective response rate of up to 80% in advanced melanoma with IO102-IO103 plus nivolumab. Which interpretation is most consistent with the dossier's stated limitations?
Q4When the dossier contrasts IO102-IO103 with pembrolizumab, what key distinction about their modes of action and research roles does it emphasize?
Q5Which statement best reflects IO102-IO103's regulatory and safety status as described in the dossier?

10Sources

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