How long does it take for resistance to Ziv-aflibercept to appear?

As a treatment drug for rectal cancer , the efficacy of aflibercept (Ziv-aflibercept) is self-evident. However, as a targeted drug, the word drug resistance of the receptor aflibercept will inevitably appear. Patients who have tested their genes and are suitable for the use of the receptor aflibercept are concerned about how long it will take for drug-resistant mutations to develop after taking aflibercept and how to deal with them. According to relevant data, how long does resistance to aflibercept generally last? Patients will develop resistance within a few months or 1 year after using aflibercept. In fact, there are many patients with rectal cancer because the drug resistance rate changes drastically after a few years. Everyone has a different physique and has different drug resistance reactions. If you feel unwell, please inform your doctor in time.