Enzyme May Boost Power of Chemo to Kill Mesothelioma Cells

Keep an eye on the investigational enzyme PEGPH20. It wasn’t developed to treat mesothelioma, per se.

However, it might emerge as an important companion medication you’ll someday take to increase the effectiveness of your mesothelioma chemotherapy treatments.

Right now, PEGPH20 is being targeted for use in cases of non-small cell lung cancer and pancreatic cancer.

The commonality between pancreatic cancer, non-small cell lung cancer and mesothelioma is a substance called hyaluronan. In all three of these cancers there is an abundant supply of the stuff.

Hyaluronan — HA, for short — is basically a sugar. It helps cancer cells grow by enveloping them and functioning as hardened armor plating.

Mesothelioma chemotherapy drugs have a hard time piercing this plating. This partially explains why mesothelioma chemotherapy works only sometimes, and not always particularly well.

This is where PEGPH20 comes in. It causes HA to degrade on contact. Before long, the armored shielding surrounding a cancer cell has more holes in it than a slice of Swiss cheese.

These holes provide access ports for the mesothelioma chemotherapy drugs to pass through and be able to really penetrate down deep into the cancer cell. At least this is what happens in theory.

May Test Against Mesothelioma Cells One Day

To prove the theory, the company has been sponsoring a clinical trial of PEGPH20 in pancreatic cancer cases. The randomized Phase 2 study is titled “The Halozyme Pancreatic Cancer Study — Halo-109-202.”

The chemotherapy agents being used are paclitaxel and gemcitabine. Some of the clinical trial participants are receiving PEGPH20 together with those chemo drugs, while others are taking the chemo drugs without PEGPH20.

All of the clinical trial participants have stage IV pancreatic cancer and have received no prior treatment.

PEGPH20 is administered to the participants twice a week for the first chemotherapy treatment cycle. After that, the enzyme is given once a week during each subsequent chemotherapy cycle.

Each and every time, PEGPH20 is administered intravenously — the same as the chemotherapy drugs.

Interim results indicate that median progression-free survival among the PEGPH20 cohort is twice that of the non- PEGPH20 group.

Participants who received chemotherapy alone went 4.3 months before cancer growth recurred, while those who received chemo plus PEGPH20 went 9.2 months before the cancer came back.

Another PEGPH20 Trial is Underway

The maker of PEGPH20 a short time ago launched a second clinical trial, this one focused on individuals with non-small cell lung cancer.

This trial is open to not just stage IV patients, but also those in stage III. No interim results are yet available.

PEGPH20 is made by a San Diego, California, biotechnology company called Halozyme Therapeutics.

The company is focused on developing and commercializing novel oncology therapies that target tumor microenvironments. PEGPH20 makes up the lead proprietary program, but is not Halozyme’s only venture.

The company also is working with a number of pharmaceutical giants to develop a drug delivery platform that Halozyme invented. The platform permits subcutaneous delivery of biologics and small-molecule compounds that currently can only be given by intravenous infusion.