I'm an Australian patent attorney with a mechanical engineering degree with honors (which I understand may be like a Masters in the US, anyway its 4 years of technical study. I also did 3 years of history and languages).
I can't answer your question about pharma manufacturing. I can say that, at least in Australia, the patent attorneys I know are split between those with degrees such as mine and those with a PhD almost exclusively along technology lines.
The chemists, biochemists and geneticists all have a PhD before they start studying to become a patent attorney. Conversely, the electrical and mechanical engineers mostly do not have a PhD - perhaps due to a perception that those in this field with a PhD live in ivory towers and are not practical. What the good engineers do have is at least a few years solid industry experience - which means they can relate to clients and understand their inventions well. Manufacturing experience is invaluable. They can read the drawings easily, understand why something was done in a particular way etc. Have a look at the profiles of attorneys at my firm to see what I mean in terms of background/experience. http://www.wadesonip.com.au/intellectual-property-experts/
As a chemical engineer, you straddle the divide. My advice would be to look at the profiles of attorneys in larger US firms, who have less than 10 years experience (attorneys with 30 years experience may only have a technical diploma!)and see what their background is. If they are chemical engineers practicing in pharma etc, they may tend towards a PhD. If they are more towards gas/oil or other industries, they may not. You should look at whether their practices are what you want to do.
Don't forget about patent agents - they are not attorneys as such. They have all the training needed to draft and prosecute patent applications at the USPTO, just not in Court. The pay is not usually quite as good, but I understand you don't need the law degree as such (remember I'm in the Australian system, not the US!) And of course, law degrees are very expensive, both in time and money.
Becoming a patent attorney/agent is all about getting that first job - you have to have the qualifications the firm wants. So, looking at job advertisements for patent attorneys would be another excellent way to go, try http://patentlyo.com/jobs for a jobs board that is pure patents. If you can get the first job without the PhD, that's the way to go! Once you're qualified, other firms are much less likely to worry about whether you have a PhD or not, as becoming a patent attorney is not easy to do. Remember starting at a bigger firm is good for the resume as you will be presumed to have better training than with a very small practice.
wishing you the best of luck