Moderna Surges 5.23% on Strong RSV Vaccine Data, Ranks 259th in $0.42 Billion Trading Volume

Moderna (MRNA) rose 5.23% on Sept. 22 with a trading volume of $0.42 billion, ranking 259th among U.S. stocks by volume. The biotech firm's shares gained traction amid updated data on its respiratory syncytial virus (RSV) vaccine candidate, which showed improved efficacy in a Phase III trial. The vaccine demonstrated 86% effectiveness in preventing severe RSV disease in older adults, outperforming initial trial results announced in June.

Analysts highlighted the significance of the RSV update, noting the vaccine's potential to capture a substantial share of the $4 billion annual RSV market. Moderna's collaboration with Lonza for manufacturing capacity expansion also drew attention, with the partnership expected to scale production to meet demand for both RSV and seasonal influenza vaccines. The stock's performance contrasted with broader market weakness, as investors focused on the company's near-term commercialization prospects.

To run this back-test accurately I need to pin down a few implementation details: 1. Universe • Should we consider all U.S. listed common stocks (NYSE + NASDAQ) or a narrower group (e.g., only the S&P 500 constituents)? • ADRs, ETFs and other non-common-stock listings—include or exclude? 2. Ranking metric • “Daily trading volume” based on number of shares traded, or dollar volume (shares × price)? 3. Execution convention • Buy at today’s close and sell at tomorrow’s close (typical close-to-close test), or buy at tomorrow’s open and sell at the same day’s close? • Any slippage/transaction-cost assumption you’d like applied? 4. Performance aggregation • Do you want the results shown as an equal-weighted daily portfolio of the 500 names (i.e., 0.2 % weight each) with daily rebalancing? Once these are settled I can build the data-retrieval plan and run the back-test.