Monday , October 23 2017

Heart benefits of good diabetes control last for decades – Old red dye shows promise as new cancer foe

Six-and-a-half years of intensive diabetes control may protect against heart attack and stroke for the next 30 years, according to long-term results from a US trial that began in the 1980s.

Participants in the Diabetes Control and Complications Trial (DCCT) who strictly controlled blood sugar after being diagnosed with type 1 diabetes had over 30 percent lower rates of heart disease, heart attacks and strokes over the next three decades compared to those who got standard care in those early years.

“Efforts to make intensive diabetes management attainable at a young age must continue so as to reduce the rates of life-threatening cardiovascular disease over the life span for patients with diabetes,” the study authors conclude in the journal Diabetes Care.

Starting with good blood sugar control after being diagnosed with type 1 diabetes helps to reduce the likelihood of diabetic complications like blindness and kidney disease.

Diabetes

The DCCT ran from 1983 to 1993, and involved 1,441 volunteers with type 1 diabetes, ages 13 to 39 years old, as well as 29 medical centers in the United States and Canada.

Past studies have shown that in the first 10 years, early intensive diabetes therapy significantly reduced the risk of developing cardiovascular disease (heart attack, stroke, cardiovascular death, angina and the need for coronary artery disease treatment).

Now, Dr Rose Gubitosi-Klug from Case-Western Reserve University in Cleveland, Ohio, and colleagues report the results over two decades after the trial concluded, when more than 1,300 patients no longer had their blood sugar management dictated by the study protocol.

While blood sugar levels were better for the intensive therapy group during the study, there were only trivial differences in blood sugar control in the ensuing years between those who originally had intensive diabetes therapy and those who had the standard diabetes therapy of the time.

Yet, after an average of 26 years, the risk of having any cardiovascular event was 30 percent lower in the patients who originally received intensive diabetes therapy, despite this lack of difference in blood sugar control in the later years.

The risk of a first nonfatal heart attack, stroke or cardiovascular death was 32 percent lower with intensive, versus conventional, therapy.

Blood sugar control in the later years mattered, too — each 10 percent improvement in control (measured by hemoglobin A1C) was associated with a 17 percent reduction in the risk of a cardiovascular event.

Gubitosi-Klug did not respond to a request for comments.

John B. Buse, a diabetes expert from University of North Carolina School of Medicine in Chapel Hill, told Reuters Health, “Though we were hopeful that intensive management of diabetes would be associated with sustained benefits, I do not think anyone believed that the benefits would be sustained over 30 years of follow-up in the DCCT. It suggests that there is great value to improved glycemic control for whatever period of time that it can be sustained.”

Even so, he said by email, “The one remaining but unanswerable question is: Does this comparison of intensive management in the 1980s and 1990s, as compared to what today would be viewed as totally inadequate care, really predict the benefit of improved control though best practices in 2016 as compared to less good practices today?”

Buse thinks it’s “best to assume that the answer is ‘yes’í and that targeting near normal blood glucose levels and accepting an A1C of 7 percent should be the aim of diabetes care today.”

Dr Rozalina G. McCoy, another proponent of intensive diabetes therapy from Mayo Clinic in Rochester, Minnesota, said, “For me, as a practicing primary care physician and endocrinologist, this study reinforces the importance of starting patients with type 1 diabetes on treatment early and utilizing every possible resource to help patients and their families manage their diabetes in a way that not only achieves and maintains glycemic targets, but is also sustainable by being affordable and tolerable (e.g, with least possible hypoglycemia and burden of treatment).”

The study results “will help me engage patients and families in informed and shared decision-making by showing them that there truly is benefit to reducing hemoglobin A1C,” she told Reuters Health in an email.

Modern cancer drugs supercharge immune systems, target specific gene mutations and pack modified viruses into vaccines. Amid the increasing sophistication, one investigational treatment stands out for its simplicity.

Rose Bengal, a cheap industrial chemical that turns yarn and food bright red, has been used as a diagnostic staining agent for some time. Now, some scientists are looking at its potential to fight various forms of cancer.

Cancer

At the forefront is Provectus Biopharmaceuticals Inc, which is testing a reformulated version of the industrial dye on melanoma, the deadliest form of skin cancer. The Knoxville, Tennessee, company reported promising results in a small melanoma study.

While some doctors are encouraged by the research, government approval is years off and not guaranteed. The company must replicate its early results on a bigger scale, and a US Food and Drug Administration decision is not expected before 2019.

Rose Bengal’s potential against cancer was discovered by accident. The salt was first patented in 1882 as a wool dye and has been used for years as a diagnostic stain in tests for jaundice in newborns and to detect eye damage.

In 1998, scientists who later founded Provectus were looking for a safe photoreactive agent to use in an investigation of lasers against cancer. Rose Bengal fit the bill.

As it turned out, the Rose Bengal solution appeared to work on its own to dissolve tumors when directed injectly into them, recalled Provectus Chief Technology Officer Eric Wachter, a former scientist from Oak Ridge National Lab who co-founded the company. “It made the lasers obsolete.” (RTRS)

In a study of 80 people with advanced melanoma, half of the patients who had all of their lesions injected appeared cancer free after an average of two months. A year later, 11 percent continued to show no signs of cancer, according to a report published the Annals of Surgical Oncology.

The lesions were destroyed from the inside with no apparent harm to healthy tissue, researchers said. Reported side effects included injection site pain and blistering.

Final results from an ongoing 225-patient melanoma trial of the experimental drug compared to chemotherapy are expected in early 2018. The hope is that the drug, known as PV-10, will prevent melanoma from progressing beyond Stage III, in which the disease has spread but not yet to other organs, and allow patients with more advanced cancer to live longer.

“This is one of the really neat examples of what we call repurposing, taking drugs that been around for years … and suddenly realizing that they may have an oncologic value,” said Dr Vernon Sondak, head of cutaneous oncology at the Moffitt Cancer Center in Tampa, Florida. Sondak has been running clinical trials for Provectus.

The company also has begun a melanoma trial of the drug with Merck’s Keytruda, a treatment that works by helping the immune system fight cancer, to see if the combination has a more pronounced effect on slowing disease than either alone.

Doctors said they hoped PV-10 combinations would not create the additional toxicity seen with some other combination therapies because of its mild side effect profile.

In addition to PV-10 destroying injected skin lesions, researchers noticed shrinkage in untreated lesions and tumors as far away as the lungs, suggesting it may also provoke an immune system response.

“We’ve come to the conclusion that it is immune based,” said Dr Sanjiv Agarwala, chief of medical oncology and hematology at St. Luke’s Cancer Center in Bethlehem, Pa. Agarwala, who has been conducting PV-10 trials funded by Provectus, also has run several cancer immunotherapy studies, including on Keytruda.

Dr Patrick Hwu, an immunotherapy expert from MD Anderson Cancer Center, said PV-10 is one of several interesting tumor ablation techniques in the works.

“The biggest value will be if it can affect distant disease,” said Hwu, who is not involved in PV-10 testing.

Pfizer holds a co-patent on PV-10 for use in combination therapies, and Boehringer Ingelheim has secured right of first refusal on use of the drug against liver cancer in China, the companies told Reuters.

Provectus estimates the cost of PV-10 from laboratory to approval will be about $100 million, a fraction of the more than $1 billion in research and development for a new drug that the industry often cites to defend against criticism that medicine prices are too high.

Provectus executives say the small development tab — along with relatively low manufacturing costs and easy handling requirements — could make PV-10 a less expensive new treatment. But the final decision on price is likely to be made by a bigger drugmaker, as Provectus plans to put itself up for sale once its drug is approved.

The $95 million company trades at about 49 cents per share, off a high of 98 cents last April, on very small volumes, possibly reflecting investor uncertainty over the drug’s prospects.

By Will Boggs MD

Check Also

‘Cancer awareness key factor to tackle disease’

KUWAIT CITY, Feb 1, (KUNA): Launching awareness campaigns on cancer is a key factor to …

Translate »