Sep 19, 2025
Applications
How Hydrogels Are Reshaping Cancer Treatment
Sinan Gölhan
Founder & CEO at GelTech Labs
“Hydrogels? You mean those squishy things in bandages?”
Yes — but they’re also revolutionizing how we treat cancer.
In recent years, hydrogels have gone from passive wound dressings to smart drug depots, immune modulators, and even tumor-microenvironment engineers.
In this issue, I’ll explore:
How hydrogels are used in cancer therapy today
Real-world examples in the clinic or clinical trials
Why hydrogel-based approaches are outperforming traditional delivery methods
What it means for innovators in biomaterials and oncology
Why Traditional Cancer Therapies Fall Short
Most chemotherapies and biologics are delivered systemically — via IV or oral routes — which means they circulate through the entire body to reach the tumor.
This approach comes with well-known downsides:
Toxicity to healthy tissue
Dose-limiting side effects
Low concentration at the tumor site
Poor retention in solid tumors
Rapid clearance of immunotherapies or mRNA drugs
Hydrogels solve many of these issues by delivering therapies locally, precisely, and over time — transforming how we approach everything from glioblastoma to melanoma to pancreatic cancer.
How Hydrogels Are Used in Cancer Treatment
1. Localized Chemotherapy Delivery
Hydrogels can be injected or implanted directly into or near a tumor site, releasing cytotoxic agents over hours to weeks.
Example: GLIADEL® Wafer — a biodegradable polyanhydride hydrogel implant loaded with carmustine (BCNU)
FDA-approved for glioblastoma multiforme
Placed directly into the resection cavity after surgery
Bypasses the blood-brain barrier, delivers high local dose with fewer systemic effects (source)
2. Post-Surgical Recurrence Prevention
Hydrogels are used to line tumor resection sites and release anti-cancer drugs to kill residual cells.
Example: OncoGel (ThermoDox + injectable hydrogel carrier)
Thermosensitive PLGA-PEG-PLGA hydrogel + paclitaxel
Under investigation for esophageal and brain cancers
Forms a gel at body temp, prolongs drug exposure at the tumor site (clinical trial NCT00496866)
3. Immunotherapy & Cytokine Delivery
Hydrogels are used to localize immunomodulators like checkpoint inhibitors, IL-2, or GM-CSF, boosting immune response without triggering systemic inflammation.
Example: STING-activating hydrogel (Saha et al., Science Translational Medicine, 2020)
Injected directly into tumors
Releases immunostimulants like cGAMP to activate innate immunity
Enabled full tumor rejection in mouse melanoma models with no systemic toxicity (study link)
4. Hydrogel Cancer Vaccines
Some hydrogels are engineered to slowly release tumor antigens + adjuvants, training the immune system to recognize and attack the cancer.
Example: Eli Lilly/Ankyra Therapeutics Hydrogel Immunotherapy Platform
Hydrogel depot that holds IL-12 and tumor antigens at injection site
Prevents systemic IL-12 toxicity while achieving local immune activation
Recently partnered with Lilly in a $180M+ deal (source)
Why Hydrogels Are Better (In Many Cases)
Compared to traditional drug delivery methods, hydrogel-based systems offer clear advantages:
🎯 Drug Localization: Traditional therapies circulate throughout the body. Hydrogels can be placed directly at the tumor site for higher local concentration and better tumor targeting.
🛡️ Lower Side Effects: By avoiding systemic circulation, hydrogels reduce exposure to healthy tissue — meaning less nausea, fatigue, immune suppression, and other dose-limiting toxicities.
⏳ Sustained Release Profiles: Instead of a burst of drug all at once, hydrogels offer controlled, time-released therapy — hours to weeks depending on the design.
📍 Longer Retention at the Target Site: Hydrogels physically remain in or near the tumor, allowing continuous local exposure to the therapeutic payload.
💉 Fewer Doses Needed: Patients may receive a single hydrogel injection or implant instead of daily IV infusions — improving comfort and adherence.
The Catch: Complex Testing Requirements
These systems are powerful — but sensitive to formulation parameters like:
Swelling behavior (controls diffusion)
Degradation rate (controls therapy window)
Biocompatibility & byproducts (regulatory requirement)
Testing and validating these properties across real-world conditions is essential for regulatory approval and clinical consistency — and it’s exactly the challenge we’re addressing at GelTech Labs.
Final Word
Hydrogels are no longer just supportive materials — they’re active agents in the fight against cancer. And as we enter the era of personalized medicine, they’ll play an even bigger role in delivering therapies exactly where — and when — we need them.
If you’re developing a hydrogel for oncology, I’d love to connect and learn more.