The positive Q1 financial results indicate a strong financial position for AC Immune, which is always a good sign for investors. The partnership with Takeda, a major player in the pharmaceutical industry, for the development of an Alzheimer's disease immunotherapy is likely to be viewed positively by the market. This collaboration not only validates AC Immune's technology and approach but also provides financial and developmental support, potentially accelerating the path to market for their Alzheimer's treatment. Both of these factors are likely to boost investor confidence in the short term, driving up the stock price.