Biotechnology ETFs

Porges suggests that investors who still want to enter the space should target bio-tech large- and mid-caps with more stable earnings and product lines.

Looking at ETF market capitalization allocations, IBB follows a traditional market-cap weighted indexing methodology, with large positions in large-caps. BBH has a heavier emphasis on mid-cap holdings. PBE leans toward mid- and small-cap biotechs.

iShares Nasdaq Biotech

For more information on the biotech sector, visit our biotechnology category.

Max Chen contributed to this article.