We are currently in the middle of the month and Christmas is coming. This is a quiet period and normally there will be little movement here. We can therefore conclude that the biggest moves of the month have now come to an end within a week. Assuming that the price closes around this value at the end of the month, we see a pretty good respectation around 200. This may mean that the price will first fall back to the 175 area and then, potentially, break through all time highs.
On the weekly timeframe we see that the 200 level is enormously respected. This is a strong signal that the price could fall back to the indicated 175. This does not necessarily mean that this must necessarily go there, but a correction towards that area would be very common. The moment the price lingers around 175 and creates a solid bottom, there is again a great chance of a price move up and certainly also the possibility of making a new all time high. The next publication is in February, which means that the biggest fundamental influences stay out until that time.
If you have GLPG in your portfolio you should not be surprised when the stock drops a little in the next months. That would be a healthy cycle of the market. In the short term it would therefore not be a very bad idea to sell GLPG relatively close to 200. On the medium / long-term price timeframe the 200 was your ideal target.
If you want to buy GLPG; I would wait a bit. It is not the most favorable price to get in. There are plenty of other stocks that are more attractive to buy.