Sodium bicarbonate

A pilot study of oral bicarbonate as an adjuvant for pain reduction in patients with tumor related pain.

 

Location: Lee Moffitt Cancer Center, Florida (USA) 
Collaboration: Dr.Robert Gillies, MD; Dr Robert Gatenby; MD

 

Normal cells use glucose to produce energy by combining it with oxygen. When not enough oxygen is present, e.g. during vigorous exercise, normal cells convert glucose into lactic acid instead. The acid is then pumped into the fluid around the cells. This increased acid level is why muscle pain occurs after exercise. Unlike normal cells, cancer cells convert glucose to lactic acid even when enough oxygen is present so that tumors as well as normal tissues around them are usually very acidic.

It is generally thought that cancers cause pain because they disrupt and destroy normal tissue. However, a number of recent studies have shown that nerves that sense pain in the body are highly stimulated by acid. Some studies have shown that most of the pain caused by cancers is actually due to the amount of acid they produce which stimulates the pain fibers. In other words, it is possible that some and perhaps even most of the pain that people feel due to the presence of a cancer is caused by the acid the cancer produces.
Studies have shown that giving sodium bicarbonate, which is a substance the human body ordinarily uses to maintain normal acid concentrations, to experimental animals can significantly reduce the acid levels in and around tumors.

In this study it was investigated if sodium bicarbonate can be used in people with cancer to reduce acid levels in their tumors and also reduce the pain that the tumors cause. Bicarbonate is used by the body as a physiological buffer. This means that it tends to keep the pH level of body fluids at around 7.4. In this study we asked the patients to increase their ability to buffer acids by taking sodium bicarbonate powder with water. In order to significantly affect the acid concentration in tumors, a larger dose of sodium bicarbonate – about twice as much – than that usually given for heartburn is required.

The purpose of this study was :

• To determine how well people tolerate sodium bicarbonate taken orally in higher doses than those usually given for heartburn.
• To determine if sodium bicarbonate can reduce cancer-related pain.

The study is still ongoing, accrual is slower than anticipated.
More information about this study (NCT01350583) at www.clinicaltrials.gov.

 

 

A phase 1 study of oral sodium bicarbonate in patients with unresectable pancreatic carcinoma treated with gemcitabine.

 

Location: Lee Moffitt Cancer Center, Florida (USA)

Collaboration: Dr. Gregory Springett, MD, PhD (principal investigator)

 

Normal cells use glucose to produce energy by combining it with oxygen. When too little oxygen is present (such as during vigorous exercise) cells convert glucose into lactic acid instead. The acid is then pumped into the fluid around the cells. This increased acid level is why your muscles often hurt after exercise. Unlike normal cells, cancer cell convert glucose into lactic acid even when enough oxygen is present and so the tumor as well as normal tissues around the tumor are usually very acidic (the so called Warburg effect). We have found in experimental animals that this acid helps the tumor grow by breaking down the normal tissue next to the tumor. It can also reduce the ability of the immune system to kill the tumor cells and may even limit the effectiveness of some chemotherapies. We have found that administering sodium bicarbonate orally reduces the acid levels in and around tumors and can decrease their growth rate.

In this study a new treatment for pancreatic cancer that combines the standard medication used to treat pancreatic cancer, gemcitabine, with sodium bicarbonate was examined. This combination of drugs has never been used before.

The purpose of this study is to:

• Identify the largest dose of sodium bicarbonate that can be given with gemcitabine.
• Determine if the combination sodium bicarbonate and gemcitabine produces better control of pancreatic cancer than gemcitabine alone.

The study accrued 8 patients and has been completed because 2 patients have experienced dose limiting toxicities and 5 were not compliant due to taste or intolerability.   A new IMD application (Investigational New Drug application) with an improved formulation will be submitted to the FDA.
More information about this study (NCT01198821) at www.clinicaltrials.gov.