It seems odd to me that the first order of business for ABBV is a $1.5 billion share buy-back. The number of ABBV shares issued was determined by the number of ABT shares. A buy-back is supposed to increase share price, but some analysts argue that it simply demonstrates a lack of a business plan. ABBV is a pure pharmaceutical company, and its goal should be to discover, develop and market novel drugs. With that much money, they could purchase or partner with a number of start-up companies with promising drug targets and/or drug candidates. My opinion, it's a poor way to begin operations.
Since the buyback is planned to occur over a period of SEVERAL YEARS, your comment doesn't make much sense, unless your hope is that the share price will remain low over that entire time period. The only logical argument for buybacks is to increase earnings/share - but that doesn't happen if the company simply holds the shares - or uses them as compensation for management.
This is ofc always a question to ponder. I always rather look if the companies are sitting on cash without any battle plan while buybacks do not raise the red flag you are concerned with. Because buybacks can attract enough investors to bring in new cash to buy the stock and unlocks the company's horizons to do a more expencive or a streak of acquisitions. That's the way I look at it.
I think you're taking a very short term view of a sector, pharmaceuticals, that is of a very long term nature. The sort of acquisitions and partnerships needed to provide drug development candidates do not depend on stock price, but on the sort of cash used up in a buyback. You may have an understanding of market psychology, but I don't think you have any understanding of the underlying pharmaceutical business. For the continuing success of ABBV, buyback of stock is more likely a negative than a positive. If management is more concerned with short term share price, they are not competent to manage a pharmaceutical company.