How Scientists Shot Down Cancer’s ‘Death Star’ (NY Times)

Sakina Lakda
February 12, 2021

After 40 years of research, scientists are launching a new drug called Sotorasib, which can switch off one of the most common cancer-causing genetic mutations in the human body. This mutation is known as KRAS-G12C and is found in 13% patient of lung cancer patients. The drug was tested in patients with the most common type of lung cancer, called non-small cell lung cancer (NSCLC) to which in there is no cure in the advanced stages. The drug made the cancers shrink significantly in patients with the mutation.

On average, tumours in the patients stopped growing for seven months. In 3 out of 126 patients, the drug seems to have made the cancer disappear entirely so far. Side effects included diarrhoea, nausea and fatigue.

Food for Thought

What are the stages a drug must undergo in order to be released into the market?

Before a drug is released to market, there needs to be pre-clinical research and clinical research trials (phase 1-3) to see if the drug is effective and if there are any side effects. Then the drug needs to be approved by the regulating authority. What information do you think the regulating authorities need to know about Sotorasib before it can be approved? What are the risks vs benefits that must be weighed? What might stop a drug from being approved?

The distribution of KRAS G12C in the population: 

The KRAS G12C mutation was most commonly found in patients with NSCLC (13.8%) compared to other cancers. Among patients with NSCLC, the mutation had the highest prevalence in the white population (13% had the mutation) and black population (10.9%), whereas only 3.6% of Asian patients with NSCLC had the mutation. It was also more common among females. Why is this information relevant when developing a drug? Do you think white female patients who have NSCLC will have the best results with Sotorasib? This study looked for the mutation in 32,138 patients in total, but 27,738 of those patients were white whilst 2,045 were Asian. How may this change the way you interpret the results?

Practice Interview QUestions
  1. Drugs can often have mild and sometimes severe side effects. Can you list some factors that doctors would take into account when assessing whether to prescribe a patient on a particular drug?
  2. In terms of medical ethics, which pillars may be affected by the premature release of a drug without sufficient clinical trials?
  3. Role Play: You are a doctor delivering news to a 60 year old patient who has been diagnosed with advanced non-small cell lung cancer. He is a long-term smoker. He is very anxious about the results of his recent scan. How would you break the news of his diagnosis?

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