Drugs will have their side effects, but when patients started to suffer from bad side effects, something has to be done.  

In comes the Genitourinary (GU) Oncology team at the NCCS, who noticed a troubling amount of their renal cancer patients suffer from side effects of grade 3 or higher as a result of the drug Sunitinib. 

Their observation started a seven year study on the dosage and corresponding toxicities observed. Beginning in 2007, study revealed conclusive results in reducing toxicities for Asian patients with metatatic renal cell carcinoma (mRCC) or cancer that has spread beyond the kidney. 

Introduced as a drug for mRCC in Singapore since early 2005, Sunitinib's FDA-approved dosage of 50mg once daily for four weeks, followed by a two-week break in a six-week treatment cycle, was proved to link to high toxicity levels and patient risk.  

The GU Team at NCCS then started observing 127 patients  as a clinical registry, and provided the patients with a modified dosage of the drug. 

The results were favourable - 59 percent of the participants experienced severe side effects as compared to the previous 85 percent; 24 percent than 58 percent required reduction in dose delays; and 35 percent rather than 70 percent of patients requiring dose reduction during their course of treatment. 

Dr Tan Min Han, visiting consultant at the centre's Division of Medical Oncology and a member of the GU team, shares the importance of the findings. 

"This is an affirmation to our efforts and we believed that the continuous understanding of real world outcomes will reap greater benefits for our patients." 

He added, "The findings would not be possible without the collaborative nature of our tertiary healthcare counterparts."  

The new treatment regimen for sunitinib has been accepted by oncologists in Singapore. For the patients, this would mean an estimated 30 per cent reduction in fees because of the lower dosage. The median overall survival rate (OStotal)  was 27.4 as compared to 21.8 months among patients receiving the attenuated dosage. 

This research was published in Clinical Genitourinary Cancer journal in November 2014 and supported by a grant of $50,000 from the NCC Research Fund.