Aside from these articles being hard to read
I'm not sure they even make sense. It's claimed that the EEA provides the restrictions. The EEA is NOT the EU. Our membership of the EU has little effect on the rules we'll follow in the EEA, because it is a different supranational body. It's bloody confusing, but it also is kind of key to the article, isn't it?: Supranational european bodies (Wikipedia)
So "intellectual property rights owners that place their goods for sale in one country within the European Economic Area (EEA) generally cannot use their intellectual property rights to prevent these goods from being bought and sold within the EEA." will be completely unaffected by a brexit, unless my understanding is flawed.
As for the proposed advantages of the loss of price arbitration if we leave the EU, that's an advantage to whom, exactly? arbitration is actually a good thing, economically. It means the consumers aren't screwed by artificial price differences from place to place - so your average UK national is only charged £10 for antihistamines the same as your average French national is charged 13EUR Rather than say, £500 and 20c where some guy pays and the other guy freeloads.
Now in medicines, I agree we do need some dampeners on arbitration due to the fact that the third world cannot afford the development costs to do with drugs and the first world can. By all means vaccinate in both - I'm happy for the first world to pay 3x as much for their vaccines to cover the cost of vaccinating the third world as well. It benefits the human race as a whole. But the EU is comprised of largely 1st world countries. Price arbitration between the lot of us is surely the fairest way to do it? Why would we vote to leave for this reason?