Any biotech firm that even has a loose association with the treating of tropical diseases or rare communicable diseases will do very well in the coming years.
There is no question that climate change will lead to a large amount of people traveling away from their homes to find a safer environment to live in. This mass migration from tropical areas will bring these once rare diseases into the concentrated populations of cities and significantly increase the demand for drugs to treat these diseases. While it is really a niche market today it is one that is growing in response to this threat, and profitability will come as no surprise once wealthier populations are afflicted.
This is also not to mention the growing mosquito population and their spread globally into more populous regions in such a way that increases the spread of things like malaria, dengue and many other such diseases. Not only will firms who work to create drugs for these diseases see an increase in revenue, but also companies in the realm of genetic engineering, who work on making brands of disease carries which enter the population and slow the growth of the disease vectors.
Climate change will bring on many changes and only time will exactly which companies will succeed and if regulation will limit the profits of the drug companies who work to fight the shifting human geography.