Ivonescimab, arginine, zebrafish: how much do you know from this week's medical news?

Six questions from fresh health news: a lung cancer treatment, ambulances, the immune system and generational health. This is not medical advice, just a knowledge refresher.

1. Why did the FDA reject the lung cancer treatment ivonescimab?
2. How many new ambulances will the Hungarian National Ambulance Service buy from the 2027 budget?
3. Which amino acid's low level may weaken the immune system against tumours and viruses, according to a recent study?
4. In which animal was a marketed osteoporosis drug shown to prevent harmful mineral deposits in the spine?
5. What did the University College London study find about the health of 50-year-old Gen X versus baby boomers?
6. How many times more likely are men using anabolic steroids to need erectile dysfunction medication?