Taking Herceptin (trastuzumab) for nine weeks is just as effective in HER2-positive breast cancer patients as taking the same drug for 12 months — as is currently recommended. A British study now says the shorter treatment course also leads to fewer cardiac side effects and may save the country’s National Health System (NHS) millions of pounds.

The study, “Multi-arm Cost-Effectiveness Analysis (CEA) comparing different durations of adjuvant trastuzumab in early breast cancer, from the English NHS payer perspective,” appeared in PLOS One.

Nearly 25 percent of early stage breast cancers have activating mutations in the HER2 gene, a feature that makes them more aggressive. In patients with such cancers, adding the anti-HER2 antibody Herceptin to the post-surgery chemotherapy regimen increases survival rates and delays the recurrence of disease. But the drug is expensive and causes side effects, the most serious of which are potentially life-threatening heart problems.

While drug manufacturer Roche recommends that women should receive Herceptin for a year after surgery in agreement with its clinical trials, studies have suggested that 9 to 10 weeks on Herceptin would be just as effective.

To assess this, researchers at the University College London looked at eight studies conducted in Europe and in the United States. They performed a combined analysis of two of those studies, which followed patients for five years after they received Herceptin, and included 3,344 HER2-positive breast cancer patients. Of that total, 2,149 had received Herceptin for 12 months, 54 received the drug for nine weeks, and 1,131 were not given Herceptin at all.

The team looked at three outcomes in the five-year period: overall survival rates, rates of secondary cancers, and patients who had died of a heart attack. In addition, they extrapolated the patient’s disease status and quality of life for 50 years into the future so as to assess the therapy’s possible long-term effects.

While the study proved that adding Herceptin to the adjuvant chemotherapy regimen helped patients, it also showed that the nine-week and 12-month treatment duration had similar survival benefits. But patients taking Herceptin for only nine weeks showed fewer cardiac side effects.

Looking at the incidence of breast cancer in 2014, the team found that 46,085 new breast cancer cases were diagnosed in that year alone, 5,678 of which were eligible for Herceptin. The team estimated that if all these patients had received a nine-week treatment course instead of the 12-month course, the NHS could have saved £132 million at 2014 prices.

“This work provides additional evidence for Herceptin as a drug for breast cancer treatment. Where it differs from other work is that it shows the potential benefits of nine weeks of treatment instead of 12 months, in terms of both reduced costs and improved patient outcomes,” lead author Dr. Caroline Clarke, UCL Institute of Epidemiology and Health Care, said in a news release.

“Overall, our results suggest that the 9-week option could be the best option for both patients and the NHS, as it is apparently just as effective as the 12-month duration, safer in terms of leading to fewer cardiac side effects, and cheaper.”